Nick Laslett

@CharlotteJ, here is the text of a post I made recently about the sound insulation topic. Here is a really good YouTube video from Ali Dymock that covers a lot of the concepts for sound proofing a wall.

@TerryE, talks about the thermal bridge detail of the plinth for his MBC insulated raft in this thread and on this blog post. @Oz07, you are right to highlight the importance of the junction between the raft and the superstructure. People also need to consider the requirements for external doors. These details should really be designed into the insulated raft.

Hello All, Just to confirm I will be there at 6.30pm, as planned.

You need to look at the performance tables from British Gypsum or Siniat GTEC, etc. This picture shows the acoustic performance of a simple 12.5mm timber stud wall, 35 is the key number. Next picture shows more variables, double boarding or insulation 16km/m3. Number now is higher than 35, this is better. You can find these performance tables from most plasterboard manufacturers, sometimes in a document called the White Book. Sound insulation is a complicated topic. There are three types of sound transmission that you are trying to control. I have a post about it here already.

GSE trays comply with MCS 012 certification. I used Midsummer for my supply. Trina panels comply with MCS 012. My electrician is MCS qualified, so he signed off the install.

@flanagaj, we have Thermowood Ash from QTD. https://www.qtdgroup.com/cladding This material will lose all its colour and go grey just like normal timber cladding. The advantages of the Thermowood vs normal timber are: 1. Dimensional stability 2. Greater resistance to insects and fungi. That is it. Downsides: 1. Cost 2. Installation time. Thermowood needs pilot holes and is fixed with screws. You can’t use nails, the timber is very dry and splits easily. If you use timber paint on thermowood, it will last a lot longer as the thermowood does not expand and contract as much as traditional cladding, so the paint doesn’t crack as easily. We used Osmo Clear UV oil for first year, but that stuff only lasted a year before needing a re-coat. Considering OSMO tinted UV oil this year. Or going with a paint. This has also been recommended. https://rubiomonocoat.co.uk/durogrit Picture of when it was first installed. I will post a more recent one later.

@Drellingore, I used the Stroma SAP software to do my “as designed” submission in 2021. This was a free download at the time. Here is a good thread discussing various approaches to SAP This thread links to the current download I think. Then this is another good discussion about using the Stroma software. You needed to edit the PDF output to remove the DRAFT watermark.

@Dave Jones, my expectations are so low at this point, that it will be hard to be disappointed!

I really rated the Senior Architectural PURe line, well engineered frames. They are a relative newcomer to the domestic market, but very strong in Commercial buildings. https://www.seniorarchitectural.co.uk/senior-opens-doors-into-the-domestic-market/

@flanagaj, this is an area where you could potentially save some money. You can get good u-values from 2g windows. For aesthetics we had to go with 2g, we wanted the crittall style look and steel windows are another level of expense. Our windows are only 1.3 u-value, but the coating on the inner leaf of the outer pane is what makes all the difference to how the window feels. This is a pretty standard thing to have and it helps reflects back your body heat. We have Smart Alitherm Heritage windows. A lot of companies use their systems but market them under different names like Duration and Cherwell. In the UK windows market you have system manufacturers, underneath them you have local fabricators, then you have installers/retailers. Sometimes the installer will also be the fabricator. The fabricators supply the local retailers. There are many exceptions to this. You could have the best window system, but be let down by the fabricator or installer or both. This website does good coverage of the aluminium windows market and will list a lot of system manufacturers. https://www.doorandwindowexperts.co.uk/aluminium-windows/who-makes-the-best-aluminium-windows/

That sounds great. Next Thursday works for me. Thank you for hosting.

@zzPaulzz, I agree with Alan, your build is at an interesting stage. I would love to take a look.

We have used George Barnsdale for our front & back doors. This is an example of the cill detail, ignore the measurements. The 94mm door frame sat on the 150mm concrete core of the ICF block. Then we have a cill extension piece extending over the outer leaf of EPS by about 25mm. My understanding is that this would usually be fixed with a screw from the bottom going into the frame from the outside. They were unable to do this, because the EPS was in the way, so they screwed the cill extension piece from the inside through the door frame. Hope that makes sense. For out French doors, these are aluminium and have aluminium cills large enough to protruded past the EPS.

This is the thread I was thinking of with an excellent post from @HerbJ breaking down the MVHR numbers for another member.

BR requirement for supply is based on no. bedrooms. That is what you see in the first line of the Paul quote. BR uses a different criteria for extract. There is possibly an “and/or” requirement in BR to satisfy the criteria. MVHR are not designed to satisfy UK building regs, but to give you a pleasant house environment (forgive gross oversimplification). But if you install the right MVHR unit it will comply with both Building Regs. The MVHR thread here does explain it, and the spreadsheet notes cover the calculations in detail. Just like the heat loss topic, you can do your own calculations. I will find the link. First post has the MVHR_sizing spreadsheet, and ventilation building regs document. This is what I posted in 2020 to help myself to understand the building regs requirements circa 2020. This was from the Vent Asia website at the time.