Fire proofing ceiling of garage under house

[Rickard Dwiggery]

Read a thread above about putting 2 layers of 12.5mm plasterboard on a ceiling to create 30mins fire barrier.

In order to make my garage fire proof shall I do the same or are there more stringent regs for garages under houses?

It seems strange because when we bought the house, the estate agents described the area as 'under floor storage' - it seems a very minor job to stick some plasterboard up and add an immediate £5K to the value of the house by giving it a 'garage'. If it was so easy why didn't the previous owners do it?

(Everything else checks out btw, access through rear of property along small lane which we have right of way across).

Regards

Rick

[Michael McNeil]

I imagine regs vary from one place to another. I believe that the stuff you need is pink having a layer of fibreglass in it. Make sure you cross the joints in the first layer with the second so smoke won't seep through.

[Rickard Dwiggery]

Thanks, I'll look for that. I'll be fitting heat detectors in there as well for added security.

Rick

[nightjar]

Cost, inconvenience, something you have missed? Check that the wall between the house and the storage area also meets the fire requirements - a 100mm thick brick wall probably won't - and that, if there is a door in that wall (which has to be a fire door), it has at least a step up into the house that is at least 150mm high.

Colin Bignell

[Bob Mannix]

Yes but can't give the details. Steel beams have to be encased for example as do plastic pipes which run through the ceiling.

The regulations have to deal with the possibility of a high temperature petrol based inferno.

I would contact the BCO pronto otherwise you may be way off regs.

[Christian McArdle]

If there is a door into the main property, then the floor must be dropped a certain distance below the rest of the ground floor. This is to discourage heavy exhaust fumes from entering the house proper. The door itself must be a fire door, not cut (or cut using the approved manufacturer's procedure) held in a frame with intumescent strips.

Christian.

[Christian McArdle]

The vast overwhelming majority of people use garages as storage areas. Simply boarding the area to make it look nice, but without labelling it as a garage or providing a garage door would satisfy most people. You might even bring it up to habitable standards. That really would increase value. When I had my last house, with integral garage, conversion to habitable space was worth around 15K, but was probably only about 5K in work, as the walls were already DPCed and the ceilings were plasterboarded (and artexed!). The only work required was installing an insulated concrete floor (plenty of room to do so), replacing the garage door with wall + window, plastering/insulating walls and installing electrics/heating. Most of these jobs are simple DIY, too, except maybe the bricklaying or any wet plastering.

Christian.

[Michael McNeil]

That's what I'd do as most modern houses are fitted with cheapo garages that are unusable if you haven't got an open topped car.

Hmmm.... I wonder if there is a market for that. I could do that sort of thing as a speciallity and get rich quick.

[Neil Jones]

discourage

procedure)

I always thought this was the case, but when I read the relevent regulation it implied that having a 100mm high threshold in the doorway would comply.

Have I got the wrong end of the stick?

Neil

[Christian McArdle]

I don't know, but can't see why a high threshold would be that much less effective in preventing heavy floor hugging exhaust fumes entering than a dropped floor, so it would seem like a sensible rule to me.

Christian.

[Huge]

I had always assumed that it was to keep burning petrol out, rather than fumes.

(We have an integral garage.)

[Rickard Dwiggery]

Just what my Father suggested. However this would mean digging out the floor as there is only about 6' head height under the house. We want to move on in the summer so haven't got the time to do anything more substantial.

There is no internal access to the garage, you have to walk round and down the steps to the rear of the property. I reckon if I board it up and make it look like a Garage it will be up to the next owners to get it surveyed. If it can't be used to store a car then, as an earlier poster said, it's still a great storage area.

Regards

Rick

[Neil Jones]

I've had another look at the regulation - it's more than implied:-

(From Document B)

9.14 If a domestic garage is attached to (or forms an integral part of) a house, the garage should be separated from the rest of the house, as shown in Diagram 25. Note: The walls and floors shown in Diagram 25 are not compartment walls and compartment floors and that the 100mm difference in level between the garage floor and the door opening is to prevent any leakage of petrol vapour into the dwelling.

The diagram show 100mm difference between the garage floor and the bottom of the door and the text beside it says

"wall and any floor between garage and house to have

30 minutes fire resistance; any opening in the wall to be at least 100mm above garage floor level with a FD30 door"

I wonder if you need to have the 100mm if you specify diesel-only vehices and fuel cans for your garage :-)

Regards

Neil

[Hugo Nebula]

On Wed, 25 Feb 2004 18:52:23 -0000, a particular chimpanzee named "Rickard Dwiggery" randomly hit the keyboard and produced:

The requirements are:

1. The walls and floor over, and any supporting structure, must have at least 30 minutes fire resistance. For a floor, a layer of 12.5mm p/bd with the joints taped and filled, and a tongue and grooved boards over will give 30 mins. Any steel beams must be boxed in with 2 x

12.5mm p/bd (joints staggered, taped and filled). Masonry walls will give 30 mins, as will stud walls with 12.5mm p/bd either side (or 2x12.5mm on one side).

1. Any ducts, or any plastic drainage pipes over 40mm diameter, must be boxed in with 2 x 12.5mm p/bd. All gaps must be sealed.

2. Any doors between the garage and the house must be fire doors (FD30 standard), and there must be a 100mm high non-combustible step or threshold down to the garage.