Fixing stud wall to solid floor

[rushty]

I have a 1950s bungalow with a solid concrete floor. There is a DPC about 25mm below the top finish, which is a hard brown substance.
Am I ok to screw the sole plate of stud wall through the DPC?

 

[PrenticeBoyofDerry]

It's not recommend to break DPC, how long is the wall could you fix the plate with adhesive rather than screw it?

 

[rushty]

The wall will be roughly 10' with a door in the middle. I was dubious about using adhesive.

 

[Richard C]

Two choices;
Drill holes & inject either a liquid DPC or silicone into them, insert the plugs, coat the screw & the bottom of the sole plate before you drive them home, it will self seal.
Or;
Use shorter screws & cut the plugs so you don’t penetrate the DPC, just use more of them. Vertical studs @ 400 centres between the floor & ceiling plates will provide more than enough bracing on 20mm deep fixings, it won’t be going anywhere. You could use some grab adhesive in addition to the short fixings but I wouldn’t rely on adhesive alone.

If you’re working any distance from the exterior walls I doubt there will be much moisture under there now anyway. I had to dig up parts of my 1960’s floor (similar to yours) during renovation works (drainage) & it was bone dry under the DPC; I reinstated the DPC with a liquid membrane after the work & have no indication of damp problems in the 3 years since.

 

[noseall]

I would not lose any sleep over a few punctures. It's not like you are piercing a water filled balloon or owt!

That said we always tack a piece of dpc to the underside of any sole plates we fix to a concrete floor.

 

[Chukka63]

im with nosall.i was waiting for a sensible approach without going OTT.the wall will be still be here when youre long gone.

 

[Richard C]

im with nosall.i was waiting for a sensible approach without going OTT.the wall will be still be here when youre long gone.

So you think mine wasn't a sensible approach then

 

[noseall]

im with nosall.i was waiting for a sensible approach without going OTT.the wall will be still be here when youre long gone.

So you think mine wasn't a sensible approach then

I don't think Chukka is fussy about whom he insults Rich.

 

[Chukka63]

im with nosall.i was waiting for a sensible approach without going OTT.the wall will be still be here when youre long gone.

So you think mine wasn't a sensible approach then

not what i meant at all.

 

[rushty]

Thanks guys. If I need to tack DPC to the bottom of the sole plate I may as well use liquid (per Richard) and drop some in the holes at the same time.

 

[freddiemercurystwin]

im with nosall.i was waiting for a sensible approach without going OTT.the wall will be still be here when youre long gone.

So you think mine wasn't a sensible approach then

I don't think Chukka is fussy about whom he insults Rich.

 

[alittlerespect]

Hi

You may find that what you have come across is not the dpm but a layer of adhesive used to stick down a parque floor, with a building of this age it was usual practice to put down a minimum 50mm (2" in old currency) sharp sand and cement screed on top of the oversite concrete to level the floor.

The construction detail should be 100mm clean hardcore, 50mm sand blinding, dpm turned up perimeter wall and onto dpc of internal wall, 100mm oversite concrete, 50mm sharp sand and cement screed to level the floor, then the flooring laid in a pitch based adhesive.

If not convinced check out 'www.sika.co.uk' or email your enquiry to '[email protected]'

They do adhesives that stick/bond tighter than sh*t to a blanket!

Regards

 

[Chukka63]

just drill the holes and screw ya base plate to the floor.the screws will be surrounded with plastic plugs(use 2).done.you will be dead before anything untoward might happen.

 

[stuart45]

If you think about Timber frame construction, the frames were often fixed by nailing through the DPC into the sole plate without any problems. A DPM was quite rare on concrete floors before the 1965 Building Regs.
Screwing through the floor should not be a problem.