Air Tight Tape around Windows

mfceiling

I have a quick question for those in the know.

I'm looking at a house at the minute. Built about 2-3 years ago - left as a shell. Plastered, wired and plumbed.

Other houses in the development i've been told were given a B1 rating when finished.

I haven't spoken to the seller/developer/builder directly but i'm guessing no airtight tape was used at the windows.

If not, would anyone recommend -

(a) strip off the reveals, airtight tape, fit new reveals and skim.

(b) tape over existing reveals then re-skim.

Thanks in advance.

newbie2013

Always wondered how is it possible to make my own 2005 build air tight. Is it even possible to do it once a house is finished.

hexosan

My sisters house is in the same position, build approx 7yrs ago and no Airtightness strategy was involved.
Drafts around all the windows, at the base of the wall behind the skirting and the hollow core was never wrapped. She had a suspended ceiling and when you remove one of the spots and place your hand up into the void you can feel the wind blowing.

MicktheMan

mfceiling wrote: »

I have a quick question for those in the know.

I'm looking at a house at the minute. Built about 2-3 years ago - left as a shell. Plastered, wired and plumbed.

Other houses in the development i've been told were given a B1 rating when finished.

I haven't spoken to the seller/developer/builder directly but i'm guessing no airtight tape was used at the windows.

If not, would anyone recommend -

(a) strip off the reveals, airtight tape, fit new reveals and skim.

(b) tape over existing reveals then re-skim.

Thanks in advance.

(c) if drylined with insulated plasterboard on bare block inner leaf, remove drylining, sand/cement render to bare block wall, tape wall to floor and wall to window/door frame.

mfceiling

MicktheMan wrote: »

(c) if drylined with insulated plasterboard on bare block inner leaf, remove drylining, sand/cement render to bare block wall, tape wall to floor and wall to window/door frame.

It's a timber frame house mick.

Wondered was it worth knocking off the reveals, taping, boarding and skimming.

Or is there a tape that can go on that can be skimmed over and painted then?

MicktheMan

mfceiling wrote: »

It's a timber frame house mick.

Wondered was it worth knocking off the reveals, taping, boarding and skimming.

Or is there a tape that can go on that can be skimmed over and painted then?

I hadn't considered tf.

In that case, I would remove reveals, tape, board and skim. And then have a quick air tight test done to make sure all is okay (incl walls, ceilings etc)

mfceiling

MicktheMan wrote: »

I hadn't considered tf.

In that case, I would remove reveals, tape, board and skim. And then have a quick air tight test done to make sure all is okay (incl walls, ceilings etc)

Sound advice Mick...i'll talk to the builder first....finish seems very good so tape may have been used. Going from C3 to B1 - is there a big difference?

hexosan

Not to draw the thread off topic but if your plastering below the floor insulation for airtightness is it sufficient to just plaster the external walls or do you have to plaster the bottom of the internal walls as well.

MicktheMan

mfceiling wrote: »

Going from C3 to B1 - is there a big difference?

Apologies for the vague answer.
Depends on what's done to move the grade and what you consider "big". There is also an improvement in comfort level which isn't really taken into account in the ber grading system. For instance, having a draught free, appropriately ventilated home with moderate insulation levels will, imo, be more comfortable and easier to keep warm that a "super" insulated home full of draughts (i.e. no air tightness measures taken). In the above example, the former may well have a poorer rating than the latter.

MicktheMan

hexosan wrote: »

Not to draw the thread off topic but if your plastering below the floor insulation for airtightness is it sufficient to just plaster the external walls or do you have to plaster the bottom of the internal walls as well.

I don't understand what you are asking here.

hexosan

MicktheMan wrote: »

I don't understand what you are asking here.

I'm laying floor insulation prior to pouring my screed and I'm plastering down below the floor insulation to seal this junction. After the screed is in the plasterers can plaster down onto this.

MicktheMan

hexosan wrote: »

I'm laying floor insulation prior to pouring my screed and I'm plastering down below the floor insulation to seal this junction. After the screed is in the plasterers can plaster down onto this.

You seal the junction from the external wall to the finished floor screed, not the junction to the subfloor. Remember, the air tight barrier needs to be on the warm side of the insulation.

hexosan

MicktheMan wrote: »

You seal the junction from the external wall to the finished floor screed, not the junction to the subfloor. Remember, the air tight barrier needs to be on the warm side of the insulation.

Thanks for that.

WhatNowForUs?

MicktheMan wrote: »

Apologies for the vague answer.
Depends on what's done to move the grade and what you consider "big". There is also an improvement in comfort level which isn't really taken into account in the ber grading system. For instance, having a draught free, appropriately ventilated home with moderate insulation levels will, imo, be more comfortable and easier to keep warm that a "super" insulated home full of draughts (i.e. no air tightness measures taken). In the above example, the former may well have a poorer rating than the latter.

Hi would you be able to explain this further for me. I would presume that a super insulated house would have limited drafts where as a house with moderate insulation would be more likely generate more drafts.

BryanF

WhatNowForUs? wrote: »

I would presume that a super insulated house would have limited drafts where as a house with moderate insulation would be more likely generate more drafts.

insulation and air-tightness are two separate things

MicktheMan

BryanF wrote: »

insulation and air-tightness are two separate things

Couldn't have said it better myself:)

If you are building and don't understand this point then seek advice (from someone experienced and independent) sooner rather than later.