HELP!!!! 3 quick questions!! All guidance would be very much appreciated.

[meadhran]

Was wondering:-

In terms of new build timber frame houses, are there any regulations/standards re:

1) Loft insulation, i.e. minimum depth of, should the insulation only be laid between rafters or should it be also laid at right angles overlying rafters?

2) Is there specific underlay which should be used beneath carpet/vinyl which is laid on a concrete floor? Specifically is felt underlay beneath a carpet and no underlay beneath vinyl laid on a concrete floor acceptable?

3) When installing a gas fire is it acceptable for the builder to remove the thermal insulation from the wall to accommodate the fire, meaning that the fire sits directly in front of the external brick work and the thermal insulation is compromised (or non existent as it's been removed to accommodate the fire! Having major impact on room temperature.)

Any help/guidance/assistance would be greatly appreciated.

Thanks for reading.

[SteveF]

Hi there

1) Depends how old your property is with relation to thickness of insulation.
2) The situations that you mention with regards to underlay can be seen as acceptable by some people although the concrete floor should be a power float finish. However there are no standards with which you could challenge the builder to my knowledge.
3) This sounds to be totally wrong and should be addressed ASAP.
How old is your property and was the fire installed from new.

SteveF

[meadhran]

Hi there

1) Depends how old your property is with relation to thickness of insulation.
2) The situations that you mention with regards to underlay can be seen as acceptable by some people although the concrete floor should be a power float finish. However there are no standards with which you could challenge the builder to my knowledge.
3) This sounds to be totally wrong and should be addressed ASAP.
How old is your property and was the fire installed from new.

SteveF

Thanks for replying. The house is 18 months old. In terms of fire it was an "extra" purchased at time of buying. Builders (Persimmon, Bathgate) have undertaken some remedial work; changed external wall mounted flue, replaced open fire with ceramic fronted one (not what we wanted!), however the cold/draught is still a major problem for us. The actual fire part itself sits directly in front of the external brick, that is where the thermal insulation has been removed. Builders say that won't do any more as "fitted to spec" although they have offered refund of cost if sign confidentiality agreement but say "deal is off" if I contact NHBC (as per my other post which you replied to). I want to go the NHBC route but I'm worried that they'll back builders and we'll be left with the fire, cold and draughts whereas if took money could spend it getting fire removed and wall returned to original specification, i.e. insulated!!!

[SteveF]

Hi there

So is the fire is a balanced flue type (where the flue round metal flue is seen directly behind the fire on an external wall)?

Do you know if any alterations were made to the timber frame other than the removal of the insulation i.e. have any vertical studs been affected?

SteveF

[SteveF]

Hi

Sorry forgot to mention, in response to your question regarding loft insulation your house should have a minimum of 270mm. This is the minimum requirement to comply with building regulations.
The rolls are generally installed with a layer between the roof trusses directly onto the plasterboard and a subsequent layer running at 90' to the first layer.

SteveF

[meadhran]

Thanks again for replying.

Yes, that's exactly the type of fire it is. Persimmon say studs would have been cut or removed (I can't remember which, sorry) and that the fireplace would have then been "boxed in" due to the studs being affected. They haven't actually checked this though they're adamant it would have been done this way.

Re loft insulation, I'll need to check depth, but it's laid between the trusses only and not cross wise as well. Is it just preferable to have it run both ways or is that some thing which I could pursue to have rectified as a breech of building regulations?

Appreciate your time and advice.

[SteveF]

Hi

With regards to the alterations made to the timber frame in order to insert the fire;
I would be concerned that this may have affected the structural integrity of the internal wall if not executed correctly. This in my opinion should be checked by the timber frame manufacturer and a structural engineer that is conversant with timber frame construction.
I am not surprised that the builder is looking to prevent you from referring this to the NHBC.

SteveF

Loft insulation is usually installed in the manner referred to in my previous mail as good practice however the primary concern would be that no gaps should be apparent between timber truss and insulation i.e. no plaster board visible.

[NewHomeExpert]

In answer to your questions:

Current regulations mean loft insulation needs to be at least 250mm. Normally this is in two layers one laid between the trusses and one at 90 degress to ensure ther are no gaps.

Regarding underlay this is not coverd by building regulations. All carpet should have a separate underlay. No underlay is required under vinyl but......if the concrete floor finish is really poor it may puncture the underlay so it is normal to "latex" these areas before laying vinyl.

You should not have the external brickwork exposed within the house. Apart from the loss of heat which you mention, this would provide a source of damp, draughts and all sorts of problems. The gas fire should have been installed infront of the internal wall and thermally insulated flue separated from the inner timber frame.

Under no circumstamces should structural timbers in a timber frame be removed without a specialist design for the alteration.

Persimmon Homes should have a standard detail for this!