Air Tightness Tips/Advice

[richo106]

We are having a bungalow renovation/conversion starting shortly and I am now determined to get it as air tight as we can. We will be putting another storey on top of the existing bungalow to create a house.

 

I won’t be installing any trickle vents, window vents or extraction fans etc. planning on having MVHR

 

Wall construction is either brick/brick or block and brick. My plan is to parge coat (including between all joists) and then dot and dab (with a continuous run of dab top, bottom and around sockets etc)

 

Air tight loft hatch

 

we are having a large oak glass front and front door - not ideal I know but anything that I need to do to help air tightness regarding the oak?

 

Sealing the skirting boards - what is the best method for sealing skirting boards?

 

Cables and pipes through walls - what is the best method for this? 
 

What is the best way to seal after the windows and have been fitted and around the window cill? 
 

what other areas do I need to pay particular attention to?

 

I am creating a list now so they will all be considered throughout the build and hopefully nothing too drastic will be overlooked.

 
I think it will be a tough ask due to my type of project but i am going to give it a good go!

 

[richo106]

Or has anybody found a guide/book that would be useful for this topic?

 

Thanks again

[Kelvin]

If you want message me your email address and I’ll forward an email I got from http://aecb.net that has some info and several links

 

 

[patp]

I will try to pm you too @Kelvinif you don't mind?

[Kelvin]

No probs

[j_s]

@richo106

I have done some major renovation. All wall junctions need to be sealed. I used blowerproof brush on paint. I also had to seal with nicks and cuts in the radon barrier where it was pulled too tight and sharp concrete edges had caused those little cuts. I used radon tape over those as well as building adhesive and tescon tape on larger exposed parts of the membrane. Took a good few hours per room to do this. I also found all gaps however tiny in the blockwork behind the plasterboard (removed), sealed all blockwork with blowerproof paint. When I had all new windows and doors fitted, the reveals were all exposed and new cavity closers fitted and completely sealed using building adhesive, expanding foam (soudal "airtight" blue) as well as large nails as we had major issues with external brick completely out of alignment with internal blockwork. I then taped over the nails. Cavity closers were all taped at the junctions. All windows had Soudal airtight foam between window and cavity closer, I was meticulous with the foam. I then taped between window and cavity closer. Finally all exposed blockwork on the reveals were painted using Blowerproof. 

 

Is there a way to refit the skirting to seal it behind and then your boards are purely decoration rather than part of the airtightness?

 

In the loft I taped all plasterboard joins, I also taped plasterboard to the wall plates. I used 25mm pir board over wall plate to plasterboard junctions, also using expanding foam to seal them in. I left space at the eaves by using 25mm pir board between roof joists. I could then use the dri-therm batts butted right up to the edges without fear of the eaves being blocked. I have a hipped roof, not fun working around the perimeter. For all light cables, I used the rubber tape that seals itself inside some conduit, I then also taped (Tescon) the cables as they came through the ceiling. No doubt that if work has to be done up in the loft on any cables then it'll be a nightmare to work with. I do not have a solution to that unfortunately.

 

House is definitely as good as it could be but with 75mm cavity insulation and questionable coverage of some of that insulation, without extreme cost I can't get it any better. I don't have much insulation under my block and beam floor, it really is a pain we have all the ventilation under the house as that must take away any potential heat in the floor in no time. Only solution I have seen is pumping insulation beads under there but it needs approval and not sure how I can go about it as well as if it will have any ramifications with radon build up (if there actually is any under the house)

[richo106]

J_s - Thank you very much for your reply and detail it’s exactly what I was after. With my building starting in 2 weeks I will be spending some evening and weekends following him around.

 

Im guessing blower proof paint will be cheaper and easier than getting my plasterers to parge coat

 

Thanks again