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On having an EPC conducted (for PV) I was told by the assessor that porches are not included –generally fair enough you may say.
The porch covers an old & drafty (but pretty) front door and about 15m2 of mostly sold wall with 0.2 walls, 0.1 floor, 0.15 roof, 0.7 window and 1.0 door to the point where is essentially at internal temperatures without heating. It is also built into an interior corner so actually reduces the wall are of the house (see diagram)
I am gutted that after all our effort to address this (last) thermal weak point the assessment assumes that the porch is outside!
Is there a magic phrase I can use when we next have an EPC conducted to explain the lunacy of this to the assessor as this is going to make achieving an A impossible!
The porch does form part of the assessment, or should do, as it should be considered as a "draught lobby", I believe. Certainly FSAP includes provision for the effect of a draught lobby on an entrance door.
FSAP does indeed have a draft loby check box (in the ventillation section) but thermally whether our porch is incuded in the heat loss is ambigous.
SAP 2009 p8 Porches: · should be included if heated by fixed heating devices; · should not be included if unheated and external. In this context ‘external’ means an addition protruding from the line of the external wall of the dwelling; · should not be included if unheated and thermally separated from the dwelling.
I might be able to argue that they should use section 3.3 U-values of elements adjacent to an unheated space
However it is rdSAP that I am primarily concerned with...
Porches: · should be included if heated by fixed heating devices; · should not be included if unheated and external. In this context ‘external’ means an addition protruding from the line of the external wall of the dwelling; · should not be included if unheated and thermally separated from the dwelling.
An unheated draught lobby in the form of an external porch should not be counted as part of the area of the dwelling. However, the door between the dwelling and the porch is a ‘semi-exposed’ element and its Uvalue should be calculated accordingly (see section 3.3).
... and from RdSAP:
Porches If heated always include (separated or not). If external and not heated, disregard. If internal, not heated and thermally separated, disregard. (‘external’ means an addition protruding from the line of the external wall of the dwelling)
I have realised that the EPC doesn't reflect our retrofitting input or in some cases levels of insulation, etc. in new built properties. I am just doing the Domestic Energy Assessor course and recall the case for adding a porch to the property is having a heating source present in the porch and no external door between porch and house, maybe ideally no door at all.
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