5.5m x 5.4m garage. Too small?

[Blib]

Hello.

As per the title. We have pp to build a 6m x 6.5m timber framed garage. However, due to the nature of the sub-soil, our engineer suggests that we need 2.5m deep, piled foundations. No one else agrees with him. Our very experienced, local builder is incredulous and our architect is more than sceptical, believing the foundations to be way over-engineered. However, the engineer is insistent and building control need an engineer's report.

So, we have three options.

A) Go along with his suggestion and spend an extra £10k+ on the piled foundation.

B) Find a more pragmatic engineer, who will spec. up a raft foundation. We are in the process of engaging such a firm.

Or.....

C) Build a 5.5m x 5.4m garage on a much cheaper, reinforced pad, which the builder insists is more than enough. At 29.7 sq m this will get us below the 30 sq metre, building control threshold.

The garage will house 2 small, classics. A 964 and a 1970, Fiat 500. The former is 4.2m long. Neither are daily drivers.

Do you own a small, double garage about this size? How have you found it to live with? Is it too small to be workable?Would it work, in your opinion?

Thank you.

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Thanks for that. The garage will be to house the cars, not to work on them. So, that's doable?

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m3jappa said:

I think so but i will try and remember to measure it tomorrow and confirm it is that size.

I'd really appreciate that, m3jappa. It's a big investment and one which I'd rather not get wrong.

Thank you.

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m3jappa said:

I just measured it (while in my boxers in the rain )

its 5.9 (deep) x5.15 (wide)

thats a touch over 30m2 so slightly less on the length (tbh my doors are inset by about 250mm) should be ok.

It has 2 doors so modern cars are a tight squeeze, however if you did just one door a modern car would be ok, we did this on our last double which was remarkably similar in size.

You are a star! Thank you so much!

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DoubleD said:

You could also measure out and mark the dimensions of the smaller garage yourself, maybe even then "park" the 2 cars inside it.

Sadly, the cars are 100 miles away and won't come up before the garage is built.

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Coxey said:

Do you know what foundations youse sits on? That would give a steer as to what you would need for your garage.

The house dates back to the C18th and so has negligible foundations.

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paulwirral said:

Option b

My preferred option.

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Thanks everyone for your input. Especially CG for your photo. From that, it appears that 5.5m x 5.4m will be big enough. If anyone else has photos of similarly sized garages I would really appreciate seeing them.

We do not intend to put anything modern in the garage. It will strictly be used to house our classics.

In the meantime, I'm still waiting for the second structural engineer to get back to the architect with his ideas. I'll update as and when.

Edited by Blib on Friday 29th November 14:00

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Thanks Hol. If I go down the 5.5m x 5.4m route the internal dimensions will be roughly similar to yours, if not smaller.

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Thanks all. Skydrive, I really appreciate those photos. That's very helpful.

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bltamil1 said:

Wow, piled foundations for a timber framed garage? I’m sure there are situations where that would be required, but not many!

If you have any ground information I would happily take a look for you and let you know if it is nonsense.

Very kind of you. Hopefully, engineer number two will spec. a raft. If he doesn't, I may well take up your generous offer.

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LaurasOtherHalf said:

Shouldn't you be consulting another engineer rather than canvassing opinions on something you don't want?

.

I am doing exactly as you suggest.

As I mentioned in my OP (see 'B' ), the second engineer is reported to be more pragmatic than the first. I'm just testing the water for the worst case scenario.

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@ PhilboSE.

I fear we are paying for our first engineer's education too!

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Thanks everyone. That Volvo certainly makes me consider.

No news yet from the new structural engineer. Even after a more than gentle "basically, is it possible?" Nudgr this morning from the architect.

We are on Suffolk time.......

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Yes, you're right. Ive decided that the smaller garage is a non starter.

So, to raft or to pile? It could make several thousands of pounds difference.

Watch this space.

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AJLintern said:

Did you decide which timber frame supplier to go with then?

In the end we've gone with a local builder who is also doing work on the house itself.

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PhilboSE said:

Blib said:

Yes, you're right. Ive decided that the smaller garage is a non starter.

So, to raft or to pile? It could make several thousands of pounds difference.

Watch this space.

Anyone who says to pile would need to justify exactly why it is required.

If time is not critical then you could dig for strip foundations to find out exactly what you're dealing with below ground and then take the advice of the BCO.

Thank you for that. Hopefully, it won't come to piles. If the second engineer concurs with the first I'll mention this.

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@PhilboSE.

Thank you for your post. I'll ask the architect to check with the original engineer about why he went with piles.

Sadly, we are rather time constrained. Mrs B. has grand plans for the garden. The landscapers cannot begin their work until the garage is almost complete. There is a complicated planting plan waiting to go. I'm already on notice as weve missed the autumn tree planting window (who knew).

Waiting for months while we test more soil is NOT an option

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The engineer took soil samples, using an auger-like implement to drill quite a way down.

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PhilboSE said:

What's the history of the site? Is it possible it is made up ground? If so and his samples suggested it went deep, then it's possible that piles are necessary. You've asked the right question, let's see what the answer is.

His answer.....

"Based on the tree species, tree heights, tree locations and the soil plasticity, the required foundation depths for trench fill foundations goes off the NHBC charts and therefore requests an ‘Engineered Design’, which basically means piling. I’ve attached our calculation sheets that show this."

He also included an image which, he says, shows why a raft is not applicable.

I'll post up his drawings later.