Problem with wrapped slab

Maxium

I type this message with almost tears in my eyes and am hoping someone can help. So we spend lots of money and time wrapping our wideslab and then a tradesperson comes on site today to mark holes to be cored in the floor and rather than lifting the membrane to mark a spot on the floor the membrane was torn back to the wall to expose the floor. I am devastated - the membrane is now only a few mm's in places and is completely gone in other places with no way to tack now to wall. What in God's name am I to do? I know I should have tacked it up straight away but too late now.

Anyway I'm wondering if the following is any saving grace? - the finished floor was poured on the slab and the membrane was brought up around the slab and finished floor and then the builder started building the second floor off the slab and finished floor (done for structural reasons). If I was to get more membrane and tape it to the slab floor and to the wall in the places it is gone would this remedy the issue? Any pointers or suggestions would be most welcome.

BryanF

Any pictures?
What did your assigned certifier have to say?

Johnnyhpipe

Do you have a design team on board who are monitoring construction on site? Please tell me this isn't a "self build"...

Your project architect will provide your main contractor with more specific guidance than that suggested by strangers on a forum.

homewardbound11

You Poor thing. My air tightness layer was drilled through by the hrv company and also the electrician. Made the air tightness company come back and re do the air tightness an billed the hrv company for their mistakes. Only proper order as it was made clear to all parties before hand

homewardbound11

Have you windows in and can you get a preliminary air tightness test done. You might find out with a smoke test the there is leaks. Might save you money.

Maxium

Sorry no photos as broke camera phone during week too - having no luck!!! Also no windows in yet and roof is not on so a blower test at this stage is not possible.

And yes this is a 'Self build' - don't know why that's an issue. I feel we can do a good job on the airtightness and we're using an air tightness consultant but doing the work ourselves. Haven't talked to the consultant yet as he's away on holidays so hopefully he'll have a solution next week but just thought someone on here could say if my proposed solution was even a runner and put my mind at rest for the weekend.

Thanks Homewardbound - will get this fixed somehow and talk to the tradeperson involved to negotiate who's going to pay for this.

theoptimist

wrapped slab?! Help! I'm educating myself on airtightness as I seem to be the only person on site to think its important, however my hollowcore slabs are already down, 3 inch concrete screed poured. I know i need my membrane on roof, plaster on walls, tape on joints around windows and doors... I had thought the concrete screed would be reasonably airtight and I would just have to worry about the joint between floor and wall...what else am I missing? I'm a self build with no overseeing architect and an old school builder who doesn't believe in insulation, believe me when I say I know this is not ideal! But I have to do the best I can with what I have so please forgive my ignorance....

ferryman35

I would say don't despair!!

While I'm not an expert I would say that having your finished floor in already is a help. I would suggest that you apply a mastic type sealant along the joint between the floor and the wall. A brushable one would be better - and brush it down into the joint. You can then apply a fleece tape over the mastic (before it cures) and on the wall lapping the tape over the mastic.

It would be a little tedious but i think it would give you a 99% solution at least. Time & materials to the 'expert' who caused the problem. I might be able to help you with suitable materials if you want to pm me.

We just had the floor slabs installed in our build and I thought I would clear the installer out of the site slabs and all. " We don't bother with that stuff any more" - " That's only holding us up" - "We'd have much more done by tea-time normally"

A wise old lecturer gave us the phrase years ago - "perfection is impossible and achieving it is expensive" and its one I think of everyday of our project!!

I could go on but won't!

MicktheMan

OP, do you have an AT target?
I would wait for your AT consultant to advise, as there are many ways to "repair" the damage and without viewing the situation 1st hand it isn't possible to give useful advice here.

MicktheMan

theoptimist wrote: »

wrapped slab?! Help! I'm educating myself on airtightness as I seem to be the only person on site to think its important, however my hollowcore slabs are already down, 3 inch concrete screed poured. I know i need my membrane on roof, plaster on walls, tape on joints around windows and doors... I had thought the concrete screed would be reasonably airtight and I would just have to worry about the joint between floor and wall...what else am I missing? I'm a self build with no overseeing architect and an old school builder who doesn't believe in insulation, believe me when I say I know this is not ideal! But I have to do the best I can with what I have so please forgive my ignorance....

:eek::eek:
Please don't take this the wrong way ...

I see from another thread that you are planning your build for 7 years ...yet you employ an "old school" builder who doesn't even believe in insulation, never mind air tightness. Is this a joke?

Air tightness, if it to be done properly, isn't something you go on the internet to find out about halfway through a build but needs to be planned in from the beginning which includes the selection of your building contractor / trades.

But you are where you are, so the best thing to do is to have a prelim at test done as soon as the house is initially sealed (ensuring your builder is present during the test) and take it from there. Good luck:)

hexosan

MicktheMan wrote: »

:eek::eek:
Please don't take this the wrong way ...

I see from another thread that you are planning your build for 7 years ...yet you employ an "old school" builder who doesn't even believe in insulation, never mind air tightness. Is this a joke?

Air tightness, if it to be done properly, isn't something you go on the internet to find out about halfway through a build but needs to be planned in from the beginning which includes the selection of your building contractor / trades.

But you are where you are, so the best thing to do is to have a prelim at test done as soon as the house is initially sealed (ensuring your builder is present during the test) and take it from there. Good luck:)

He's worrying about Airtightness and is planning on installing trickle vents in the windows because he doesn't believe in MVHR.

theoptimist

Ha, don't worry! If it wasn't me I'd be laughing too. Its a complete pantomime!
The 'old school builder' is my father in law, not a lot of choice in that one!! He has our best interests at heart, but I have to fight for newfangled things like air tightness!

I was a long way into the build before I realised that I was the most knowledgeable person on site on a lot of issues. (Which is quite frankly terrifying!!!) I've caught a lot of issues before they were irrevocable but this one never registered on my radar. Pretty stupid now that I think about it, and I can imagine that the only way to remedy it would be to seal both sides of the slab and the junctions between walls and slab.

I'm really not this dim, promise!
The house we're actually building is the third different design (not counting redesigns) on the third different site.
The first house was pretty well planned, the second less so and as for this one, well, lets just say I was finished putting heart and soul into designs that just end up in a filing cabinet after being dissected and finally rejected by planners! I really didn't think this one would be ever be built! Not to mention the three children that arrived in the interim!! (Not good for the decision making faculties)

Anyway, I didn't mean to hijack the thread, If anyone fancies educating me a little on sealing the junctions between top storey slab and block walls come back to me on that other thread. : )

And Maxium, good luck! sorry for the diversion.

duckcfc

Is there a course that one needs to do for air tightness?

mfceiling

duckcfc wrote: »

Is there a course that one needs to do for air tightness?

You "don't" need to do a course, but as a novice it wouldn't do any harm to educate yourself. Think there is one in Trim and one in Mountrath...Google is your friend there.

Maxium

There's a course on in a place in Athboy (google for name) but next course isn't running until mid Sept.