I live in Finland. Our house is built in 2004. We have this cellulosa insulation in walls and in the ceiling.. we have 20 cm in the walls and 50 cm in the ceiling. The reason for thick insulation in the ceiling is that I covered the ventilation pipes with the same stuff. That saves a lot of work insulating the ventilation pipes separately. There are plenty of contractors who blows this stuff around here.

Here most of our houses are so called element houses. The walls including plasterboards, fasad and windows are built in a factory. The sections are then assembled at location in a couple of days. This has been the standard since the 1980’s. There are everything from ready house models with possibility to some modification options to completely one-off designed houses. We have an completely own design. we wanted a wider house than what the standard houses normally provide with long and narrow living rooms. This requires heavier roof construction which of course costs more.

We do not live close to any major road and it is 100 meters to our closest neighbour house. It is nowadays a city planned area with only bigger lots. The cellulosa insulation combined with tripple glazed windows is in principal completely silent from normal cars passing by. There are some vibrations heard when the garbage truck empties the bins nothing else. Same goes if throw a real party. Only some minor base notes from the subwoofer can be heard in the garden.

As a refrigeration engineer, I find it interesting how reversing the heat flow in a comfort application changes where your VCM needs to go. On a coldroom, you want it air tight on the outside (warm side is on the outside). I often see condensation and ice formation in brand new coldrooms due to poor panel jointing and a lack of vapour sealing (and leaving the bloody door open!). The fabricators just silicone the internal joints and neglect the panel joints and exterior air tightness. The humid air tracks in through the gaps, condenses at the joints behind the internal alu/PVC skin, freezes, and pops the joints wider. Repeat for a year and you have a destroyed room and snowmen in the corners. Coldrooms used to use mineral wool insulation but now generally use PUR which is similar in performance to PIR but more flammable. Sometimes working with a 50K dT or more, so moisture is a concern. I think moisture issues may have gotten worse with PUR construction due to worse vapour sealing of the joints. Something worth mentioning is that PIR/PUR performance is very sensitive to installer competence. Air tightness is very important. I suspect many PIR installations have a far greater performance gap to mineral wool.

5:00 - Foil facing has two purposes. It is to reduce blown gasses from being emitted by the PIR. It is not only the PIR material which insulates but the gas it is blown with, to create the "foam". Foil is a metal and pretty much impervious to gas diffusion. It is imperative you SEAL every PIR edge with foil tape to reduce off-gassing, otherwise, over the years, you will experience thermal drift and it will not be as efficient. It is not designed to be a vapour membrane but of course will work as one. If using PIR, it is imperative to be used correctly. Otherwise use Rockwool which is far more forgiving!

Nothing much adheres well to metal, hence why tissue facings are required, to be used with bonding other materials to it. The other reason? PIR is poured into a mould, then shut, and pressure is increased. The foil helps with it sticking to everything!

Jerry,  Thank you yet again for an excellent video.  I am embarking on the self build renovation of a 250 year old oak framed Essex barn and your videos are an excellent resource 👏👏

Literally watching this as I build wooden outdoor cat shelters and i always insulate them but I'm not sure which order to layer the materials to avoid condensation/ moisture build and damp and mold. I have PIR board  underneath the subfloor frame but what can I use for the internal floor over full pine wood sheet?  Can I use aluminium bubble wrap or does it need to be raised off the wood to provide an air gap?

Great video, well done.

I like mineral wool bats and board. Except around windows and doors and stud bays next to them. Windows and doors have poor r-values so condensation can happen. So we do spray foam them. And use thermal breaks between window and door frames and framing. We also set windows and doors towards inside of house not proud of exterior.

I did a conservatory ceiling (plastics roof panels)  using the triple foil then UPVC cladding, also did the tiled floor, wood frame 2 x2 then triple foil then 12mm marine ply then self levelling followed by vinyl tiles. The sound and heat difference was amazing both in summer and winter, for a cost circa £1000, yes the cons of light loss need considering, and ensuring ventilation above the try foil. But a relatively simple DIY project 😀

Stone wool is it. Glass and stone are minerals both of them. Stone wool’s performance is better than glass wool.

@build-better-things  If you were building a flat roof that will also act as a balcony, what method of construction would you use and what type of insulation would you recommend.

This was really helpful and gave me a much clearer understanding of the insulation options available. I am renovating an old timber‑framed, clapboarded  house and have become quite stuck on how to achieve the required thermal values without creating interstitial or other forms of condensation. The advice I have received so far has been confusing and often contradictory, so your guidance would be invaluable. Please let me know if you’re available for a consultation. Thanks!

What's your thoughts on cork render for interior and error a applications?

Another highly professional construction video and gratefully received.  I would have loved to seen an explanation of the current grading/measurement system currently used to call out the insulation capabilities of these products, a refresh on the current building regs stipulation for levels of insulation in various building situations and a price comparison between the products.  An explanation of the measurement system for insulation is the most valuable of these requests - I suspect many people think this some kind of black art which uses measurement systems they are no familiar with - like 0.022 W/mK.  What the hell does this mean. Not a criticism as I think your videos are outstanding.

Got single brick extention and I've been out of the loop with architecture for far too long I wasn't sure where things stood any more in pricing and looking on places like B&Q have been useless to assess

I had been working on a Self build retirement project (Home/workshop combination)   idea for a number of years having fun designing & comparing various options on the Materials front.  My design was a simple 8m x 12m footprint (100m2 x 2 flr) suspended ground floor (Workshop) to minimise concrete use and using post foundations (x16) and the second floor (living)  ..  Gable ends with 1200 eaves and shallow 15 degree pitch roof.

Comparing steel portal frame to Various timber structural options came out surprisingly similar in material costs but certain working options gave good savings.
I discounted steel as to the complications of dealing with Steel Fabricators and using their installers.
   
So.. Timber..  I liked and have stuck with 4 x Portal frames leaving the floor area's spaces as open as possible to accomodate future use variation.  
Most of the Timber Frame option 'variations'..  ended up with the costings being very similar..  so again, using build options that were most economical won out.  12m Timber i beams for flooring and purlins (Wall and Roof)  Virtually no cutting required

Ok.. I have my Frame..  Now what..    The option I liked most is Steel faced Composite Panels (Panelsell..) with Mineral wool core insulaion at say.. 200mm thick for all walls and roofing.    This option saves on so many other Materials and Trades/men.  If Authorities wont allow industrial looking exterior it can be easily clad.  Even Full scaffolding shouldn't be necessary.

So, I am adding another option to your inclusive list.  

If this Build option was agreed by the Authorities.. 2 Tradesmen could build this very quickly using off the shelf materials for well under £50k.  
There are many complications as to using Insulation properly and effectively and 'who' to believe..  
     
My actual beef is with the 'More is Better' brigade.
   
   Looking at the manufacturers website information.. It turns out that the first 25mm of PIR has approx 80% of the insulating benefits.. The next 25mm adds another 5%..  The next 25mm.. 2%      Diminishing..
  The figures that are achieved by 200mm of PIR are un-measureable in benefit over 100mm.  In a Cost/Benefit analysis I think 100mm PIR is the 'happy' place.. but we just accept the figures and the cost and lesser space gets passed on to the eventual customer.

I had to abandon my project as I could not find any 'Professions'  interested in taking my project on and now I'm getting too old..  Ah well..

Our 2.5 bed semi is quite tight on space inside and out so I was considering aerogel as internal wall insulation between the concrete hollow blocks and the plaster board which are separated by thin wooden battens. It’s expensive, but the space thing is serious.

Jerry, thanks once again for another well-compiled and informative video. I really appreciate you always taking the time to share your knowledge. Your effort and dedication does not go unnoticed. 🙂

I used foil insulation and just stapled it as I went and when all was done added some thin batons for added safety. It's been up for over four years now.

We've used mineral wool then a multifoil barrier on the floor and roof
Initially the floor because we installed underfloor heating on the ground floor but then used it in the extension walls as well

Multifoil performs beyond it's spec with an air gap between it and wall/floor/roof

Question for anyone. I have a big room (don't mind losing some volume). The walls are plasterboard on timber frame and the outside is concrete stucco/pebble-dash. I've no idea if there's any insulation in the walls. I plan to attach some insulation board directly to the existing plasterboard and then put new plasterboard on top of that (screwing all the way through to the existing studs). Is this a reasonable idea? I'd do the ceiling too. Dunno about the floor.