5.5m x 5.4m garage. Too small?
Discussion
I'd have thought digging a test trench would be essential for gauging the ground conditions - did the engineer not do this? As I am doing my build on building notice rather than full plans, when my builder dug the trenches for my garage footings he just used his experience to judge what he thought was acceptable and got the building inspector out to look in the hole and give it a poke with a spade - seemed happy enough! 
I guess I was lucky that it became quite hard stony ground at 1m depth.
I guess I was lucky that it became quite hard stony ground at 1m depth.
PhilboSE said:
Rejected on what grounds?
Listed building combined with an un co-operative Conservation Officer. I've included doors and rooflights.Space isn't an issue - the impact on the listed buidling is despite its closest point being 10m away and not blocking any view of the house.
FFG
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.
I hope you get it sorted to how you want it. I've been waiting 10 until I'd (pretty much) finished thg house before I moved on the garage. The old one got knocked down last week and the ground all cleared ready for my new one. I live in a terraced hourse, and the garden is only 5m wide, so want to built it as wide as possible, which means between one neighbors garage to the other neighbours wall. With that in mind I was worried about having to dig down deep for footings and risking disturbing things. When we dug up the base of the old garage it was all built on a 4/5" non reinforced slab, and as far as I could tell nothing had ever moved or cracked in either the floor or walls. We're dug down a bit further and going to put in an 8" reinforced slab and hopefully going to go 5 x 7m. Im hoping that will allow occasional 2 car use, but will generally be just Mx5 and a motorbike or 2 with bench along the back wall.
Again for some scale, this is my garage and it's 5.5m wide and 5.36m deep.
This photo shows my 570s in along with a mates M5, both pretty large and both fitted despite the shelving at the back of the M5 making it a bit of a squeeze on length. When I've just got the McLaren and the MGB GT in there, there is plenty of space so two classics would fit without any difficulty.
Clearly go bigger if you can, but don't blow thousands making it bigger just for the sake of it IMHO.
This photo shows my 570s in along with a mates M5, both pretty large and both fitted despite the shelving at the back of the M5 making it a bit of a squeeze on length. When I've just got the McLaren and the MGB GT in there, there is plenty of space so two classics would fit without any difficulty.
Clearly go bigger if you can, but don't blow thousands making it bigger just for the sake of it IMHO.
Just to add two pence,
Regarding a previous comment about considering future use / buyers, and if you need to keep it under 30m² total, I'd look to ensure the internal length will accommodate a large modern car, even just one.
For example a 2018 Range Rover is 5m long, 1.99m wide.
If you build to a 6m length, allowing for half a metre spare at each end, that leaves you with 4.98m width.. With something that big parked centrally, you'd still have 1.5m either side for door swing.
You could still fit your classics in that size, with 1m between them and 0.5m to either wall.
Of course this would require a single, central door - but that's probably a much simpler option regardless..
Regarding a previous comment about considering future use / buyers, and if you need to keep it under 30m² total, I'd look to ensure the internal length will accommodate a large modern car, even just one.
For example a 2018 Range Rover is 5m long, 1.99m wide.
If you build to a 6m length, allowing for half a metre spare at each end, that leaves you with 4.98m width.. With something that big parked centrally, you'd still have 1.5m either side for door swing.
You could still fit your classics in that size, with 1m between them and 0.5m to either wall.
Of course this would require a single, central door - but that's probably a much simpler option regardless..
smithyithy said:
Just to add two pence,
…...
If you build to a 6m length, allowing for half a metre spare at each end, that leaves you with 4.98m width.. With something that big parked centrally, you'd still have 1.5m either side for door swing.
….
That M5 in my garage is only 90mm shorter than that Range Rover and without my shelving at back it would fit just fine in 5.5m, especially if the door / doors give a little more space at the nose. For me, width is more important if you're looking to park 2 cars than extra spare room at the front / rear IMHO.…...
If you build to a 6m length, allowing for half a metre spare at each end, that leaves you with 4.98m width.. With something that big parked centrally, you'd still have 1.5m either side for door swing.
….
Finally, the news you've all been waiting for......
.....we can have a raft!
The second engineer writes...
...."if the oak is removed and its current height is 10 m or less then a raft is an option with 600 mm deep reinforced edge strips and spine with a 150 mm slab"
The oak is 20 feet tall.
This means we can build the 6.5m x 6.0m garage that we have pp for.
Thank you everyone for your contributions. Especially those who took the effort to post photos. I appreciate all of the input.
I shall post some photos of the finished structure as and when.
.....we can have a raft!
The second engineer writes...
...."if the oak is removed and its current height is 10 m or less then a raft is an option with 600 mm deep reinforced edge strips and spine with a 150 mm slab"
The oak is 20 feet tall.
This means we can build the 6.5m x 6.0m garage that we have pp for.
Thank you everyone for your contributions. Especially those who took the effort to post photos. I appreciate all of the input.
I shall post some photos of the finished structure as and when.
Blib said:
Finally, the news you've all been waiting for...... .....we can have a raft!
The second engineer
If you can have a raft, you can probably have a strip foundation. The second engineer
How close to the foundation is the oak tree? And has the Engineer recommended any excavation and replacement with Type 1 or similar?
If you don't mind I'll add my recent experience for anyone reading your post in the future.
We started an extension 3 weeks ago, trenches for raft foundations dug, but the ground was made up and required piling. I had already built a 5x3m summerhouse on a slab with no issues.
Apparently this was the worst ground they had seen - I'm sure hyperbole but from several different trusted sources.
Piling company sourced and arrived in a couple of days to commence work. Probably took them 1.5 weeks.
Our extension is single story, and approx 4x8 + 3x9m in an L shape.
Piling was guaranteed to 4m minimum but required 8m in some places as the ground was so poor.
Thankfully passed by building inspector in the past week and concrete poured.
Final bill not sorted but your 10k for the area you covered at (I think you stated a 2.5m depth?) looks very, very expensive.
We started an extension 3 weeks ago, trenches for raft foundations dug, but the ground was made up and required piling. I had already built a 5x3m summerhouse on a slab with no issues.
Apparently this was the worst ground they had seen - I'm sure hyperbole but from several different trusted sources.
Piling company sourced and arrived in a couple of days to commence work. Probably took them 1.5 weeks.
Our extension is single story, and approx 4x8 + 3x9m in an L shape.
Piling was guaranteed to 4m minimum but required 8m in some places as the ground was so poor.
Thankfully passed by building inspector in the past week and concrete poured.
Final bill not sorted but your 10k for the area you covered at (I think you stated a 2.5m depth?) looks very, very expensive.
FlipFlopGriff said:
Listed building combined with an un co-operative Conservation Officer. I've included doors and rooflights.
Space isn't an issue - the impact on the listed buidling is despite its closest point being 10m away and not blocking any view of the house.
FFG
Sounds just like us - I was told that the garage size I wanted was ok, it was about 10x6m, but that as it was in the curtilage of a listed building it had to be "of architectural merit" in its own right. Which meant individually designed by an architect with the appropriate costs. They rejected clad metal and oak framed buildings equally and anything other than front opening wooden doors were out. Space isn't an issue - the impact on the listed buidling is despite its closest point being 10m away and not blocking any view of the house.
FFG
It got shelved as cost prohibitive!
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