Transcript 5. Property elements

Property Elements
In this section we will look at the different Property
Elements and how to identify and assess them.
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Property Elements
• This section of the training will cover a variety of property elements
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Flats/Maisonette
Floor and roof heat loss types
Extensions
Room in Room
Basements
Conservatories
Porches
Alternative walls
Windows
Lighting
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Flat or Maisonette
• Technically there is no difference between a flat and a maisonette in
RdSAP, the only difference is the description on the 1st page of the EPC.
Stroma Certification uses the following definitions for these dwelling types
as a guide :
• A flat is generally defined as a self contained residential unit within a
larger structure, containing several self contained unit or units all sharing a
common entrance. They are usually single storey dwellings.
• A maisonette is a dwelling which occupies 2 or more floors within a block.
It can also be described as dwelling has its own access directly from the
outside (i.e no communal corridor) but is not a stand-alone building.
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Corridors
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Corridors
• In RdSAP there are three corridor selections - None, Heated or Unheated
• You will only be asked for the corridor type for flats and maisonette’s
• If the corridor is unheated, measure the length of corridor adjacent to the
flat, including the flat door
• The length of the unheated corridor must be included in the total heat loss
(HLP) measurement for the flat
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Floor Level
mid floor flat
• It is very important to correctly identify whether the flat is:
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Basement
Ground floor
Mid floor
Top floor
• Even if the lowest floor level of the dwelling extends over more
than one floor enter it as the lowest floor e.g. ground and first
floor flat would be entered as ground.
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Definition of Enclosed Property
When assessing a flat the
detachment may not be obvious
Flat A
Flat B
Heated Flat
If the Access Corridor is unheated:
– Flat A is an end terrace
– Flat B is a mid terrace
Access Corridor
If the Access Corridor is heated:
Heated Flat
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Heated Flat
Heated Flat
– Flat A is an enclosed end terrace
– Flat B is an enclosed mid terrace
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Floor heat loss type
In RdSAP it is necessary to indicate what type of heat loss the lowest floor of
a dwelling has.
This applies to all dwelling types
– houses, bungalows, flats, maisonettes
• he options for floor type are
– Ground floor
– Above partially/intermittently heated space (Commercial Premises)
– Above an unheated space (basement, Garage)
– To external air
– Same dwelling below (vertical extensions)
– Another dwelling below (another flat below)
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Floor heat loss type
Ground floor
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This will apply to most houses,
bungalows and ground floor flats
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It simply means the lowest floor of
the dwelling is on the ground
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If a dwelling has a basement which is
not included in the assessment then
the lowest floor will not be on the
ground.
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Floor heat loss type
Above partially/intermittently heated space
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This option should be used when the lowest floor or the dwelling or part of a
dwelling (main/extension) is located over a commercial premises
It is termed partially or intermittently heated because commercial
premises are assumed to have a different heating pattern to residential
buildings
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Floor heat loss type
Above an unheated space
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This option should be used when the lowest floor of the dwelling or part of the
dwelling is over an enclosed space which is not heated, such as a garage or
unheated basement
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Floor heat loss type
To external air
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This option is to be used when the lowest floor of a dwelling, or part of a dwelling
is exposed to the outside
Some houses and flats have a tunnel passing under the first floor through
to the rear of the building
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Floor heat loss type
Same dwelling below
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To be used when the lowest floor of part of a dwelling has been built over the
existing dwelling, also known as a vertical extension.
(These will be covered later )
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Floor heat loss type
• Another dwelling below
– To be used when the lowest floor of the dwelling or part of the dwelling is
above another dwelling
– Commonly used for mid and top floor flats, but can also be used for flying
freeholds, i.e. when part of a property is located over another property
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Roof heat loss type
• As with floors it is necessary to indicate what type of heat loss the roof of
a dwelling has.
• This applies to all dwelling types – houses, bungalows, flats and
maisonettes
• The options for roof type are
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Pitched (slates or tiles), access to loft
Pitched (slates or tiles), no access to loft
Pitched (thatch)
Flat
Same dwelling above
Another dwelling above
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Roof heat loss type
• When assessing the roof type you are concerned with the dwelling being
surveyed, not always the whole building. E.g. when surveying flats.
• If you were to survey the ground floor flat of this building, what would you
think is the most appropriate statement about the roof type?
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Roof heat loss type
Another dwelling above
– This option is usually used for ground and mid floor flats. By selecting ‘another
dwelling above’ the software knows there is another dwelling above the flat
surveyed.
– This option can also be used for under-dwellings and similar building
arrangements where part of another dwelling is built over the
property surveyed.
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Roof heat loss type
Same dwelling above
– This option can be used when part of a dwelling has had an extension built
above it, known as a vertical extension. (This will be explained in more detail
later in this section.)
– The roof type simply indicates to the software that there is no heat
loss
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Extensions
• Many properties have extensions added to the original building. These
can be identified separately in an EPC. But an extension doesn’t have to
be a later addition to a property to be classified as such in RdSAP.
For the purposes of RdSAP an extension is part of a property which has
different thermal qualities to the rest of the house
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Age
Wall construction/insulation type
Roof construction/insulation type
Floor heat loss type
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Extensions
• RdSAP allows for 4 extensions, which is generally more than enough for
the majority of properties.
• If a property has one or more extensions separate information must be
recorded for each of them.
– For each part of the dwelling the following data should be collected:
• Dimensions
• Wall construction and insulation
• Roof construction, insulation and heat loss types
• Floor construction, insulation and heat loss type
• Build date
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Examples of Extensions
Different roof types
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Main property – pitched roof
Extension – flat roof
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Extension Examples
Wall construction
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Main property – solid brick
Extension – cavity
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Extension Examples
Roof insulation
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Main property – insulation at joists, 250mm
Extension – no access to loft, unknown insulation
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Extension Examples
Build date
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Main property – 1900-29
Extension – 1991-95
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Extension Over A Garage
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If a property has an extension over an unheated garage or similar unheated space, it
should be entered as an extension on the lowest floor
This is because the garage is not included in the survey, and it is not possible to leave the
lowest floor blank in the software.
The floor heat loss type should be entered as ‘over unheated space’
If the garage is heated by the main heating system, it should be
included in the survey
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Vertical Extensions
Vertical extension
Main property
A vertical extension is an additional storey to a property which can not be
accounted for as a room in the roof.
Identify the vertical extension as an extension in the software, taking separate
information for the whole extension area.
• Specify the upper floor heat loss type as ‘same dwelling below’
• Specify the lower floor roof type as ‘same dwelling above’
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Vertical Extensions
Main property roof type: pitched roof
Main property floor type: ground floor
Main
Property
Extension
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Extension
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Extension 2 Floor type: Same dwelling below
Extension 2 Roof type: Pitched roof
Extension 1 floor type: ground floor
Extension 1 roof type: same dwelling above
If the vertical extension does not cover the whole dwelling the part of the
dwelling below the vertical extension must also be identified as an extension in
order to specify the roof type as ‘the same dwelling above’.
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Multiple Extensions
Extension
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Extension
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Main
Property
Extension
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Extension
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Extension
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• Occasionally you may come across a house which has more than 4
extensions; in this situation you must ‘blend’ the extensions.
• Merge the areas with the most similar age, construction and insulation,
and make use of the alternative wall facility where appropriate.
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Mezzanine floors
• A mezzanine floor is usually an intermediate floor between two floors in a
building.
• A mezzanine floor does not extend across the whole dwelling
• This means part of the property has more floors than the rest.
• It also means that the ceiling height for part of the dwelling is
significantly bigger than the mezzanine section.
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Mezzanine floors
• When assessing a dwelling which has a mezzanine floor split the dwelling
vertically
• The split should separate the property into a part with the mezzanine and
a part without the mezzanine
• Specify one part as the main property and the other part as an extension
– In the picture the mezzanine makes part of the property 2 storey, the
remainder of the property is 1 storey.
– The 2 storey section is the main property, 2 storeys are measured and entered
into the software, with separate ceiling heights for each storey
– The single storey section is entered as an extension with just 1 storey entered
in the software, and the full floor to ceiling height entered as the ceiling
height.
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Room in a Roof
A room in a roof is defined by the following:
1.
Access must be via a permanent fixed staircase that one is able to walk
up and down facing forwards. (This does not include fixed loft ladders).
2.
The height of the common wall must be less than 1.8m for at least 50%
of the storey. Please note this does not include stud walls, gable ends or
party walls. (The common wall is a vertical continuation of the external
wall of the storey below.)
If the common wall measures greater than 1.8m for more than 50% of the floor
then it is classed as a normal storey.
Measure floor area (internally); no need to measure room height or heat loss
perimeter
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Rooms in Roof
• Would this be a room in the
roof?
• Height of wall at eaves
(common wall) is less than
1.8m
• This is classed as a room in
roof
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Not a Room in the Roof
If the 50% or more of heat loss walls at the eaves (common wall) are 1.8 metres
high or greater , the space is classed a normal floor and you will need to take the
measurements of wall perimeter (heat loss walls), room height and the floor area.
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Why have room in roof?
When you say a property has a room in roof it means the software makes the
following assumptions
– The wall construction is timber frame (i.e. the roof construction, rather than
cavity wall, solid brick etc
– The ceiling height is assumed to be 2.2m high. It can be difficult to get an
average ceiling height for rooms in roof due to the sloping ceiling
– The heat loss perimeter is based on that of the storey below. During test
surveys carried out prior to the release of RdSAP, assessors were asked to
measure the heat loss perimeter of the room in roof, but assessors came back
with such varied results for the test properties that it was decided that this
figure should be assumed to avoid too greater variation in ratings.
Effectively, when you specify a room in roof, you are saying that the majority
of heat loss for the storey is through the roof rather than the wall construction
specified in the software.
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Partially insulated roof rooms
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Partially Insulated Roof Rooms
• Presently, RdSAP assigns a flat roof area, and the remainder as wall area,
based on the floor area entered
• This is a useful estimation in most cases, however this may not prove
sufficiently accurate in certain scenarios
• If it is judged the roof room vastly differs from the default values, the
software allows areas and insulation to be recorded separately
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stud walls
gable walls
sloping parts
flat ceiling parts
• It will also be possible to indicate in the software whether the room in
roof is connected to another part of the dwelling i.e. extension.
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Partially insulated roof rooms
• in some cases it is not possible to get the Roof Room insulation levels. This
is when default values are used by the software.
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Partially insulated roof rooms
• If can only get access to certain parts of the insulation you can enter
either;
— All elements
— Flat ceiling only
— Walls and sloping parts
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Partially insulated roof rooms
• When you can get the details of ALL roof room insulation, the following
data can be entered:
– Actual area
– Actual U-value
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Room in Roof Quiz
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Is it a room in roof?
Here are a few slides of properties
• Do you think the top floor is a room in roof or another storey?
• You will be able to tell from the photo, and not have to measure the
common wall height
• Assume that there is access via a fixed staircase to the top floor of the
property.
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Is it a Room in Roof?
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Is it a Room in Roof?
Yes
• The dorma windows are built into the roof
• The common wall stops at the top of the first floor
• The common wall is 0m for the roof room
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Is it a Room in Roof?
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Is it a Room in Roof?
Yes
• This is a dorma bungalow
• The entire top floor is built within the roof structure, the cavity wall stops at
the top of the ground floor
• The dorma window is likely to be constructed using timber
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Is it a Room in Roof?
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Is it a Room in Roof?
Yes
• There are skylights in the roof of this property indicating there is an
additional floor in this property
• The common wall stops at the top of the 1st floor, so the whole top floor of
the property is within the roof space
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Is it a Room in Roof?
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Is it a Room in Roof?
• No
• The common wall stops part way up the top floor but the window height is
likely to be 2.1m
• The common wall extends for more than 50% of the storey
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Is it a Room in Roof?
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Is it a Room in Roof?
• Yes
• The dorma window indicates there is a room in the roof space of this
bungalow
• The common wall stops at the top of the ground floor
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Is it a Room in Roof?
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Is it a Room in Roof?
• Yes
• The top floor has had a loft conversion and a large dorma window has
been added
• The dorma window has a different construction type to the floors below
• The common wall type, solid stone, stops at the top of the 1st floor
• Therefore the common wall is 0m on the top floor.
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Is it a Room in Roof?
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Is it a Room in Roof?
• Yes
• Another dorma bungalow
• The top floor is built entirely within the roof structure and the common wall
stops at the top of the ground floor
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Is it a Room in Roof?
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Is it a Room in Roof?
• Yes
• The common wall stops part way up the 1st floor
• It is likely the common wall measures less than 1.8m
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Measuring a room in roof
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Measure the habitable space of the room in roof
Do not include the area behind stud walls, often used as storage space
Include the floor area of any dorma windows
A room in roof should always be measured internally
There is no need to measure the ceiling height or heat loss
perimeter
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Room In Roof Age
• You are required to enter an age band for the Room in Roof.
• The date selected will influence the level of insulation, particularly if there
is no access to the room in roof insulation. (Further details on room in roof
insulation will be covered later in the training course)
• The age band for a Room in Roof may be different to that of the main
property.
• If the loft has been converted it may not be possible to ascertain evidence
of the conversion date; in which case the original build date of the
property should be used.
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Flat in the roof
If a single storey flat is located entirely in the roof, it cannot be entered
as a Room in Roof: In this case:
– Enter the wall construction as timber frame
– The ceiling height should be entered as 2.2m
– It will be necessary to record the floor area and heat loss
perimeter for this type of flat.
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Room in roof over a garage
• If a room in roof is located over an unheated garage it should be entered
as an extension
• The dimensions should be entered as the lowest floor, it is not possible to
leave the lowest floor data blank
• Specify the following:
– Floor heat loss type: exposed to unheated space
– Wall construction: timber frame
– Ceiling height: 2.2m
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Basement
• A basement has 50% or more it’s external walls adjacent to soil.
• To be included in the survey a basement must
– Be accessed via a fixed staircase which can be walked up and down facing
forwards
– Be heated by fixed heaters or
– Be open to the rest of the dwelling
• A basement does not have to contain habitable rooms to be included in
the assessment
• Walls adjacent to soil are included in the heat loss perimeter
• Party walls should be considered as heat loss walls unless you can be sure
that the neighbouring basement is heated. You should get evidence of
this, such as a photo.
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Number of Storeys
loft space
Room in roof
First floor
Ground floor
Unheated
basement/Cellar
2 Storey House
First floor
Ground floor
Heated
basement/Cellar
3 Storey House
+ room in roof
A cellar or basement does not have to be a habitable space to be included in the
survey.
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Basement
Convention 2.05
Basements (whether to include in the assessment) states Include when
accessed via a permanent fixed staircase such that one is able to walk
downwards facing forwards and either:- - basement is heated via fixed heat
emitters, or - basement is open to the rest of the dwelling.
Does not necessarily contain habitable rooms.
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Porches
If a porch is heated it should always be
included in the EPC
• If a porch is external and not heated it
can be ignored
• If a porch is internal, not heated and
thermally separated it can be ignored
An internal porch lies within the line of the
external wall of the property, an external
porch would protrude from the external
wall, as shown in the image
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Porches
Convention 2.09 states
Porches If heated always include (separated or not). If external and not
heated, disregard. If internal, not heated and thermally separated,disregard
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Conservatories
A conservatory must have at least 50% glazed walls and 75% glazed roof
Can be classed as separated or non-separated
• If a conservatory is separated just note whether there are any fixed
heaters
• If the conservatory is non-separated then more information
is required
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Non-Separated Conservatories
A conservatory is “non-separate” if it is thermally linked to the house, i.e.
open plan or internal quality door separation
– Collect the dimensions for:
• Floor area
• Glazed perimeter
– Determine whether the majority of glazed walls are double glazed.
– How high is the conservatory? – This is measured in storeys (1 storey,
1.5 storeys, 2 storeys or 2.5 storeys.
A conservatory with an unglazed roof is a sun room and should be treated as
an extension
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Non-Separated Conservatory
• This conservatory is open to
the rest house – there is no
separating door
• This conservatory needs to
be included in the survey
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Separated Conservatory
• This conservatory has an external quality door separating it from the rest
of the dwelling
• An external quality door is one which would be suitable as a front or
back door
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Would this be a conservatory
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What about this one?
• This is a sun room, it does not have at least 75% glazed roof so it cannot
be entered as a conservatory in RdSAP
• It should be included in the EPC as an extension unless all the
construction, insulation and age details are the same as the
main house
• More than typical glazing should also by selected.
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Alternative Wall
An Alternative Wall is thermally different to main wall type and cannot be
accounted for as an extension
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Alternative Walls
• An alternative wall can be applied to all parts of a dwelling. This includes
the main property and all four extensions
• Wall area is required (excluding any apertures)
• If property is identified as a flat or maisonette, there is now an option for
a ‘sheltered’ alternative wall.
• A sheltered alternative wall is situated between the dwelling and an
unheated corridor, or stairwell. This option can only used for the main
building part.
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Alternative walls
• The convention for alternative walls is quite long, here are the key
features
– Walls of the same construction but different thickness within a building part
are not considered alternative walls unless they are stone walls
– For stone walls assess thickness at each external elevation and at each storey
and use alternative wall if the thickness varies by more than 100mm
– In the case of the wall separating the dwelling from an unheated corridor or
stairwell, where this wall is of a different construction or insulation to the
external walls (e.g. not insulated but external walls are), make it an
alternative wall and mark it as sheltered
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Windows
• There are three features of the windows in a dwelling which must be recorded:
– Window area
– Percentage multiple glazed
– Type of glazing
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Window Convention
• Typical applies if the surface area of the glazing in the dwelling is essentially as
would be expected of a typical property of that age, type, size and character. Even
if there is slightly more or less glazing than would be expected, up to 10% more or
less.
• More than typical applies if there is significantly more surface area of glazing
than would be expected (15%-25% more), perhaps because there is a large sun
room or numerous patio doors have been added.
• Less than typical applies if there is significantly less glazing than would be
expected. This is rare as homeowners tend not to take out windows, but a
property may have an unusual design with few windows.
• Much more than typical and Much less than typical should be used for
those dwellings with very unusual amounts of glazing; such as a glass walled
penthouse flat or a Huf Haus. Due to this option allowing measurements of each
window to be accounted for, it should also be used if a dwelling has a mixture of
glazing types e.g. single, double, secondary and triple.
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Percentage Multiple Glazed
• This is a calculation of the proportion of total window area which is double
or triple glazed.
• Please note that this calculation is based on total window area and not the
number of windows.
• When entering the multiple glazed percentages into the software, if the
figure is less than 100% the remaining percentage is assumed to be single
glazing.
• 0% multiple glazing will indicate the property is fully single glazed
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Glazing Type
• Multiple glazing available for selection are as follows:
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Double glazed pre 2002*
Double glazed post 2002*
Double glazed unknown
Secondary glazing
Triple glazing
• Only one glazing type can be selected from this list. If more than one type
is present at a property the most prevalent type should be selected. For
example, a property had double glazing installed in 1998 and in 2004 two
small units were replaced. Because the majority of the windows are still
pre 2002, this should be selected in the software.
*(2002 is the date for England and Wales, 2006 for Northern Ireland, 2003 for Scotland)
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Identifying Glazing Type
Double glazing can be entered as units installed before 2002 or after 2002.
The 2002 building regulations introduced a minimum standard for the
installation of double glazed units. This is indicated in a number of ways.
– Some post 2002 windows have an air gap of +12mm, although more
modern units injected with gas may have a narrower gap
– Date stamp of 2002 or later on the metal strip inside the glazing unit or
window frame
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Identifying Glazing Type
– Presence of gas fill – indicated by drill holes in the air gap
– Presence of low-e coating – identifiable with a low-e detector
– A FENSA certificate held by the owner/occupier. The FENSA website also
holds details of properties with certified windows
www.fensa.co.uk
Earlier double glazing has a more narrow air gap, less than 12mm. If it is
not possible to identify the date of installation, then the glazing should be
entered as pre-2002.
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Secondary Glazing
Secondary glazing should only be accounted for in a survey if units are installed
correctly. Temporary additional glazing, such as cling film, should not be
included in the survey.
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Triple Glazing
Triple glazing can be identified by 3 panes of glass with 2 separate air gaps
within the unit. The glazed unit will appear wide in comparison to a standard
double glazed unit.
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Window U-value and g-value
• Where documentary evidence is available it is now possible to record the
U-value and g-value for windows
• U-value
– The basic measure unit for establishing the heat loss of a construction
segment
– The unit is W/m2K
– For the whole window, not just the glazing
• g-value
– The measure of solar heat gain
– Stated as a percentage
• The best setup is high thermal insulation, which means a low U value
combined with a G value that is not too high
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Window U-value and g-value
• A U-Value or G-Value cannot be entered as a stand alone figure; both must
be known and entered in the software and used in the calculation. If not
known, existing defaults are used for the calculation
• These can be obtained from either:
– The manufacturer
– British Fenestration Rating Council (BFRC)
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Window U-value and g-value
•
•
The BFRC Scheme is the UK’s national system for
rating the energy efficiency of windows and is
recognized within the Building Regulations as a
method to show compliance for replacement
windows installation
Each window rated by the BFRC has a unique label
This label will display the following information:
1. The rating level – A, B, C, etc…
2. The energy rating eg. -13kWh/(m²·K) in this example
the product will lose 13 kilowatt hours per square
metre per year.
3. The window U value eg. 1.6W/(m²·K)
4. The solar heat gain (g-value) eg. g=0.45
5. The effective heat loss due to air penetration
(L factor) eg. 0.00 W/(m²·K)
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Window U-value and g-value
RdSAP convention 3.10 states:
U-values and g-values can be overwritten only if documentary evidence is
provided, which can be either a Window Energy Rating certificate (as defined by
the BFRC) or manufacturer’s data. The U-value is for whole window, not centre
pane.
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Window orientation
• Where the extended window data is used (when ‘much more than typical’
or ‘much less than typical’ is selected) you will now be required to record
the orientation of each window
• There will also be the option to include the U-value and g-values (if known
and documentary evidence is available)
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What is Draught Proofing?
• Draught proofing is a cheap and efficient method of saving both energy
and money.
• Draughts are similar to ventilation in that they supply the home with fresh
air. However, draughts are uncontrolled and can let in too much cold air as
well as allowing heat to escape.
• Draught proofing blocks up any unwanted gaps that let cold air in
• Types of draught proofing can include:
– Self adhesive sealant strips
– Brushes
– Spray foams (sprayed into gaps around windows)
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Draught proofing
• Previously RdSAP assumed that:
– All double and triple glazing were draught proofed
– All single glazed windows and doors were not draught proofed
• RdSAP 9.91 does not make assumptions about draught proofing, the DEA
will assess the percentage of draught proofed doors and windows
• This will allow for more accurate recommendations for draught proofing
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Types of Draught proofing
• Weather strips
• Brushes
• Self adhesive sealant strips
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Draught proofing
RdSAP convention 3.11 states:
All external doors and at least 2 windows per building should be examined
If a window is locked or inaccessible then endeavour to check another one
If the state of the draught proofing cannot be determined then take triple,
double or secondary glazing as being draught proofed, and single glazed windows
and doors as no draught stripped
Include glazing in a non-separated conservatory
The percentage of draught proofed is [(number of draught proofed windows and
doors) divided by (total number of windows and doors)] x 100
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External Doors
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External Doors
• Until now RdSAP assumed the number of doors based on the built form.
• It has also assumed the U-value of doors, but this does not account for
high performance insulated doors
• RdSAP 9.91 now requires DEAs to:
– Count the number of external doors, including doors to unheated corridors
or stairwells
– Count the number of insulated external doors
• It will be difficult to prove whether a door is insulated by a visual
inspection alone. Documentary evidence must be provided
For flats, if there is an unheated corridor the door is assumed to be for the corridor
only, i.e. not external and not included. If a flat has more than one door, the
remaining door(s) are external and included.
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External Doors
• It is also possible to enter the U-value for insulated external doors (if
known and documentary evidence is available)
• If the U-values of more than one door are known then calculate and
record the average U-value
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External Door convention
RdSAP convention 3.09 states:
An external door is a door that forms part of the heat loss perimeter of the
dwelling
A door to a heated access corridor is not included in the door count
A door is counted as insulated only if documentary evidence is provided,
which must include U-value or manufacturer reference enabling the assessor
to ascertain the U-value from the manufacturer. If there is more than one
insulated door and they have different U-values, enter the average U-value
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Lighting
• The low energy light count should only include fixed outlets
• Lights that can be removed, such as lamps, should not be
included
• lights counted as Low energy are:
– Compact fluorescent
– Fluorescent tube
– LED spot lights
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Examples of Low Energy Lights
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Lighting
Lights in the following locations are not included in the light
count:
–
–
–
–
–
–
Cupboard
Loft spaces
Separated conservatories
Porches not included in the survey
Unheated garages
Outside lights
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What if there are downlighters?
• Where there are 4 or or more downlighters/ceiling lights, divide the bulb
count by 2
• Fixed under cupboard kitchen strip lights should also be included
in the count
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Photovoltaic-PV
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Photovoltaic-PV
There are two methods to assess PV systems
• Roof percentage
• System Details (which needs further information)
–
–
–
–
Peak Power
Pitch
Orientation
Overshading
The peak power can be obtained through the MCS certificate.
Pitch, Orientation and Overshading can be assessed on site.
– 3 systems can be entered into the software per property
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Wind Turbines
•
•
•
•
The software will make the provision for only one type of turbine to be entered
If however, a property has two turbines that differ in both hub and rotor height
they must be combined and entered as one
This is done using a calculation spread sheet which takes data of multiple turbine
types and converts it into one figure
The spread sheet will be made available on the Stroma member’s area
RdSAP convention 9.07 states:
Documentary evidence is required to overwrite default values
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Wind Turbines
•
•
•
•
This is another ‘yes/no’ option in the
software
If yes, the assumption is a 2m rotor
with a 2m hub height
This option will still be available but
can be overwritten with valid
documentary evidence
The data to be collected can be seen
on the table on the right
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Any Questions?
Stroma – Property Elements
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