Basement Garage, any advice please

[Marti]

Hi petrol heads,

Doing my own house up (at last!) and having a good sized extension being built, so it may be a good time to construct a underground garage to take between 4-6 cars that would be located under my back garden and part of the rear extension. The plans for the extension is in the planning dept already and I have drawn the underground garage so I need to apply for another planning application but that's fine as not to submit too a big project all at once!! Has anybody got a underground garage and what are the good and bad and what would I need to consider also? Just thinking a large open space for cars and bikes and also housing a boiler room for the house. Cheers in advance.

 

[CatmanV2]

Heh, I thought you were the expert
Needs to be water-tight, and needs drains.
Warm, of course.
How's your trigonometry? You need quite a long ramp to get the drop to a full basement without the angles at the top and bottom either banging out the middle or the ends of the car.
Unless you install a lift

C

 

[Marti]

Heh, I thought you were the expert
Needs to be water-tight, and needs drains.
Warm, of course.
How's your trigonometry? You need quite a long ramp to get the drop to a full basement without the angles at the top and bottom either banging out the middle or the ends of the car.
Unless you install a lift

C

Hi Mr C,
Yes the construction side of things I'm fine with! I looked at the car lifts route but I think they not as versatile as a ramp,(plus silly money!!) as you rightly say you need the correct angle for a ramp, but I think I can get that by starting in my front garden and then at the side of the house where he existing garage is carry on going down till I get to the end of the house that I should be the correct depth so I can open up to from there ....well that's what I have drawn!!! If it works is another thing!!

 

[CatmanV2]

I can do the maths, if that' helps at all?

It's going to be a looooong ramp....

C

 

[Parisien]

Marti....must be someone local whose done this, go and knock on their door or ask local estate agent if any houses for sale with one, take a tape measure and list of Qs!!!!


P

 

[Marti]

I can do the maths, if that' helps at all?

It's going to be a looooong ramp....

C

That will help!.............so option #1 is a 7' garage height 2100mm with a distance of 450mm from ceiling to finished ground level giving a total of 2550mm from ground level to garage floor level. Option #2 would be a 8' (2400mm)ceiling height so a total of 2890mm . Would length of ramp would I need please,? My structural engineer has the drawings but hasn't come back to me yet! Thanks

 

[mjheathcote]

Our modern (built 2003) house has the double garage/store underneath the house, being 2/3 rds the ground floor area.
The drive is the same level as the garage, for the road we live on rises up the hill, so the garden is at ground floor level, at the opposite end to the drive.
It's completely dry and warm, with the combi boiler in the garage. No damp or condensation what so ever.
With a pair of insulated sectional garage doors, a few years ago when it was very cold if you remember, it was minus 20 outside and still plus 7 in the garage, with no heating apart from the combi boiler in there.
It's also very nice to just walk down the stairs from the hall into the store, then garage, without leaving the house, and wearing socks is just fine after completely covering the garage floor with ecotile PVC tiling!

 

[Marti]

Marti....must be someone local whose done this, go and knock on their door or ask local estate agent if any houses for sale with one, take a tape measure and list of Qs!!!!


P

We come from part of the country that nobody talks to each other let along getting past the big wrought iron gates to measure their drive!! Good idea tho!

 

[Parisien]

....then part B of suggestion...........


We live on a newish development, 20 odd homes in a cul-de-sac, I know everyone, not all socially of course....and none with an underground garage.......





P

 

[Geofflyn]

Hi petrol heads,

Doing my own house up (at last!) and having a good sized extension being built, so it may be a good time to construct a underground garage to take between 4-6 cars that would be located under my back garden and part of the rear extension. The plans for the extension is in the planning dept already and I have drawn the underground garage so I need to apply for another planning application but that's fine as not to submit too a big project all at once!! Has anybody got a underground garage and what are the good and bad and what would I need to consider also? Just thinking a large open space for cars and bikes and also housing a boiler room for the house. Cheers in advance.

Drainage and water pumps essential as well as waterproofing walls from outside the construction. This is a pretty specialist task and your insurance company will be very interested in seeing an engineers certificate

 

[safrane]

Be aware that you may need to consider soak away...if this increase the amount of area that is unable to soak up water due to it being water tight this increases the risk of flooding.

 

[Marti]

Yes thanks for that about soak away I putting storage water tanks in with the extension build but I will need to think where the overflow soak away will need to go ...5m from a building etc.......so good thinking....hmmmm!

 

[CatmanV2]

That will help!.............so option #1 is a 7' garage height 2100mm with a distance of 450mm from ceiling to finished ground level giving a total of 2550mm from ground level to garage floor level. Option #2 would be a 8' (2400mm)ceiling height so a total of 2890mm . Would length of ramp would I need please,? My structural engineer has the drawings but hasn't come back to me yet! Thanks

Need wheelbase, ground clearance and front and rear overhangs of your cars. I can pull the 4200 from the manual, but have you got anything lower?

I'll do the simple one, assuming that you have an abrupt transition from level <> ramp <> level as well.

Tomorrow OK?
C

 

[hodroyd]

It might be an idea to consider a curved drive rather than straight, this could help you with space and angles you need..!!

 

[Marti]

Yes that be fine Mr C. My sons lowered VXR may be lower but work on your 4200 for now please. Thanks

 

[CatmanV2]

No problem. Then manual doesn't list the ground clearance. Anyone know what it is off hand?

C

 

[CatmanV2]

OK
Assuming 200mm ground clearance, need, as far as I can work out, and max 18deg drop at the top, to stop the car grounding.
On your 2550mm height that gives you a ramp of roughly 70m......

There are ways to improve that, but I'm pretty sure I'm right. I need to check the actual ground clearance as it's a bit of a guess based on the 675mm to wheel arch figures that people have quoted.

I've not done the bottom ramp yet as that sounds quite bad enough until I get better data


C

 

[2b1ask1]

Catman, surely the ramp can roll in and out so not necessarily have a constant slope, this would considerably shorten the overall length and aid ground clearance issues? The middle section could be much steeper than 18 degrees and remain very drivable and walkable. Just a thought

 

[CatmanV2]

Catman, surely the ramp can roll in and out so not necessarily have a constant slope, this would considerably shorten the overall length and aid ground clearance issues? The middle section could be much steeper than 18 degrees and remain very drivable and walkable. Just a thought

Oh indeed. I think that's going to be the only sensible option. So the important thing would be that the first and last 3m are at no more than 18 deg. That should give enough space to get the car on (and probably off) the ramp (though I still want to check the ground clearance before I do the calcs for the bottom) and then match the rest of the slope to suit the length.

Even so, that's 6 m taken up. You could probably drop that to 2 m at both ends. That gives you a drop of 1200mm leaving 1690mm left to 'find' as it were.

C