Garage- Floor, Walls and foundations

[alexhayes]

Hi there,

I`ve finally got the go ahead to build a new garage. I`m planning to do most of the plans and excavation myself, get a brickie in to do the walls and possibly floor.

I could do with an opinion on the foundations.

Should I excavate the wall footings, approx 400mm x say 700mm (I know for a fact i`ll struggle to get that deep from previous excavations), and the floor slab. Then cast the slab and footings as one, thus starting my brickwork from the slab level and above.

Or

Dig footings to suitable strata, and start brickwork from there. Then cast the floor slab at a later date once the walls are up, using the brickwork as the majority of the formwork.

Never done anything like this and i'm stumbling on the first hurdle on how best to get the base and walls in place!

i`ll be getting the garage built in single skin brickwork with piers, (I`ll be reading more into insulation and vapur barriers at a later date and its brickwork over block as i can get bricks at good prices) what spacing of piers should i be working to? I have info for freetsnding walls but thats a bit overkill. I had an etsaimate of 2m but i think that might be overkill too. I need this to work out brick quantities, but also i might place a handy member across the garage for lifting out engines etc, and i`d like to plan that location. FYI looking at 20' by 12' ish size.

Roof truss's, I had imagined i`d be able to get some built, or an off the shelf solution, does anyone have any contacts or company names so i could discuss sizes and build a garage that uses a std truss.

trying to plan components now.

Planning side is with council too. Any other info which people might be willing to share is grand.

I have a pot of money to get me started, 2.5k, and then i can afford to throw about £700 per month into labour and materials. I`m in no rush to get it up.

cheers

Alex

 

[noseall]

I could do with an opinion on the foundations...............
.............Dig footings to suitable strata, and start brickwork from there. Then cast the floor slab at a later date once the walls are up, using the brickwork as the majority of the formwork.

This is the way to go.

 

[alexhayes]

Thank you, that means i can at least start work excavating myself, (once i`ve agreed a size with the better half).

I can sort out plans and components as i`m excavating.

Any idea on day rate for a pair of brickies? £300? and coverage per day? Reason being i just did some very rough sums and came out with 7,000 bricks to lay, rough calcs giving me 3.5k of labour to get the brickwork up.

Seem about right?

 

[r896neo]

Assuming you mix and labour for them (or pay an extra 50 quid or so a day and get them to bring their own labourer) 2 brickies should easily be able to lay basic block footings and 7000 bricks in a week, as long as there are not too many windows or extra details. It'll probably work out cheaper though if you use trenchfill and fill your footings up rather than build them in block.

 

[Chukka63]

standard procedure is,dig your foundations,depending on wall thickness either 450mm or 600mm wide to a depth of minimum 750mm below ground level(standard minimum depth to building regs).then,me ,personally fill 450mm of concrete .then brick/block to DPC level technically speaking 150mm above ground level.then dig out slab area.backfill with hardcore or type 1.then ya DPM and then concrete ya slab to top of bricks/blocks.then build the walls etc

 

[noseall]

The required minimum depth, regards b'regs, is 1 metre.

 

[Chukka63]

1m deep foundations in clay in this area.im not sure if the regs vary countrywide,im sure they might well do.
just call your local building control officer for your areas requirements

 

[JohnD]

The required minimum depth, regards b'regs, is 1 metre.

for a garage?

 

[Chukka63]

i would build my garage to local regs requirements.even if you dont need planning you normally need building regs or work under a building notice.

 

[noseall]

The required minimum depth, regards b'regs, is 1 metre.

for a garage?

Er no. I was being a little pedantic and pointing out to Chukka that the required min depth for footings in general (England) is 1m.

 

[Chukka63]

not here unless its clay,pedant away

 

[alexhayes]

No issue with clay heave here, and i`ll be surprised if i can get down to 750mm. I tend to hit quite a firm sandstone at about 400mm which needs a crowbar and lump hammer to break it up- which seems pointless as its a good base to build from. (Going on past experiences for the conservatory)

Cheers for input guys, i`m surprised that i may be get the brickwork up within a week, and thats cheered me up a bit if i`m honest.

Have hit a slight stumbling block with planning permission, i need to keep the ridge height to 2.5m as its within 2m of a boundry to avoid PP. This might be tricky as the eaves need to be 2.1m getting a garage door and a lintel/RSJ into the 2.1m space might be tricky. I need to have a good look at garage door heights, and see what size lintel i need for the span over the door.

Cheers guys

Any idea on No. of piers + relevant location, needed for single skin 4m wide x 8m length garage?

 

[Chukka63]

piers normally go up the side of windows/doors so sepends what windows and personel doors you are fitting.if not id say just 1 in the middle of the 8m run and the side of the up and over door would surfice

 

[alexhayes]

Brilliant, cheers- no personal door or windows (ATM). So thats reduced my calcs from 12 piers to 4 or 6 (depending where i put an RSJ) and shaved a fair number of bricks off my total.

 

[Chukka63]

whats the rsj for?????.if you need building regs they will want calcs for the steel work.use an off the shelf lintel if poss as then you wont need calcs.