New utility room

[Ash86]

We would like to make more room in our kitchen by moving our washing machine and tumble drier into the garage.

To do this I'd like to partition by means of timber stud work about 1/4 of the garage as a utility room for the above mentioned appliances, couple of cheap kitchen base units with worktop over and maybe a sink.

I would create a door way in the new stud wall for access into the garage space.

As it's a non-habitable room and has no access into the house (garage door leads onto garden) do I need to go through BC?
Will I need to raise the floor in the utility or would it not matter.

Cheers
Ash

 

[Richard C]

Creating the internal space itself is not controlled building work but a new connection to the foul drain is & any electrical work may be, depending on what’s required.

Plasterboard is not really suitable for lining stud walls in a garage without additional work. Most are single brick construction & many have no damp membranes in either the walls or floors. This means they tend to be damp especially in winter & damp is plasterboards worst enemy, even MR. If it's exposed to damp in any degree, it will warp & eventually disintegrate. There is no real need to raise the floor but if you do, drop in a damp membrane; you should also put one between the external walls & end wall studs.

 

[Ash86]

Many thanks for the reply Richard.
The walls would be skimmed if that would help? Was going to either dot and dab the one external wall of the new room or batten it off and screw plasterboard to the timbers.

Both end studs and floor plate would have DPM underneath them and where they touch external walls.

I'm a fully qualified spark so electrics no problem.

Was just unsure if I needed to raise the floor or nor as it would be difficult as the existing outside door cannot be lifted up due to the lintel directly above it, would have to create and internal step into the utility.

 

[Richard C]

Skimming would make no difference at all, it’s the gypsum in the plaster & plasterboard that hates damp. Moisture Resistant PB would probably fair better but I wouldn’t even guarantee that; additionally it must be primed before plastering but the plaster might not last long anyway. Plasterboard & single skin garages generally don’t mix I’m afraid.

You should never dot & dab on external single skin walls; because of the potential for damp the adhesive is unlikely to stand up to it. You will also get all sorts of nasty mould & crap growing behind the boards which, apart from being unhygienic, will most likely smell very musty. The adhesive dabs will also generate cold spots on the inside which will lead to condensation if you put any sort of heat in there during winter.

With garages, you really need to either batten the walls, fix a moisture barrier, some insulation & then PB but, unless it’s heated in winter the, the ambient moisture will be high & this will still cause problems, especially if you’ve no DPM in the floor. Another method would be to batten out & use cement boards not affected by damp.

 

[Ash86]

Hmm.. Sounds like a bit of a task then! Was hoping to be a cheap project.
Might be better off just chucking the washer and dryer in there anyway but have no partition or PB on the walls. Would be nice to make it a proper room but don't think I can justify the cost of cement boarded walls and insulated floor etc...

Thank you for your help Richard, much appreciated.

 

[^woody^]

Partition the garage and plaster and skim as normal. Then stick 25mm insulated plasterboard on the external walls. If the external walls gets a lot of direct rain, then coat it with a clear silicone waterproofer externally

Then self level the floor (if necessary), and carpet tile or timber board the floor.

You are not going to be troubled by any damp unless you already have a damp problem there ... and it does not sound like you have.

Vent the drier (if not condensing), and have a mechanical fan and a trickle vent somewhere

This can be a cheap job and you wont get any problems

 

[Ash86]

Cheers woody.

The garage is bone dry at the moment and was all last winter too.
How would you recommend fixing the insulated plasterboard to the external walls? Timber laths?

External walls don't get much rain due to the proximity of next doors house (two story) and the roof overhangs a fair bit.

No problem sticking in a 4" fan to give the room a bit of ventilation. Unsure on floor covering, was going to just stick a bit of felt backed vinyl down as it's cheap and practical.

Thank you
Ash

 

[Richard C]

Ther ya go, youve been told what you always want to hear

 

[^woody^]

You can use standard adhesive as recommended for the particular board you choose. Proprietary foam adhesive may be OK and quick and easy, but check that it is OK to use with the chosen insulated boards

I mentioned coating the walls as this prevents them getting too damp and then potentially debonding the adhesive, but otherwise the walls wont get damp enough to cause any adhesion problems

If you want to use laths, then do that, but then you can use some quilt insulation and normal plasterboards if you like

 

[^woody^]

Ther ya go, youve been told what you always want to hear

The thing is, the OP wants a cheap room for the appliances and he wont be sitting in there on the settee watching TV.

So he wants a compromise solution that will work without going to the [wasted] time and expense of a full conversion

 

[Richard C]

I’m fully aware that he wasn’t asking for a full conversion to “sit & watch his telly” but it won't make any difference to how long PB & plaster will last in a damp environment, especially over a single skin external wall; it will be measured in just a few years but if that's acceptable then fine. If he did watch his telly in there, he would probably heat it & it may last a bit longer but then he’d get problems with mould growth, smells, cold spots & condensation on the inside on the dot & dab to the external walls.

Insulated plaster board would be a good compromise & is something I forgot to cover but I would advise mechanical fixing in addition to any adhesive. But if the internal environment is inherently damp, the PB will still disintegrate eventually.

 

[Ash86]

Thanks guys. I appreciate both of your views.
If I attach the insulated boards to wooden battens would I need any damp proofing behind?

Like I say it's really dry and external walls are sheltered from driving rain.

I'm literally just looking for a tidy looking room to keep the washer and drier in.

I could put a small panel heater in for frost / cold protection.

 

[^woody^]

.... in a damp environment

But it is by no measure a damp environment. It is a garage.

Just a bit of context, I see damp and mould - and some really severe damp and mould in peoples living rooms and bedrooms nearly every week.

I've never ever seen any in a garage.

And central heating does more damage to plaster than anything else

The OP's plastered utility will be fine

 

[Richard C]

The OP's plastered utility will be fine

There ya go OP; no need to worry, you got it from an expert.