5.5x4m Log Cabin Concrete Base

BigBoy · 29 Jun 2017 at 21:20

Correct when it's hot and dry DPM will help the concrete cure fully.

Entai · 30 Jun 2017 at 09:25

snappyfish said:
So someone else has mentioned dpm is needed if not for damp but to stop moisture being sucked out of concrete to quickly when curing?

Yes that is one use, but for such a small slab with zero weight on it (a garden shed/log cabin is nothing) the rate at which the slab dries and cures is not of consequence.

If you were in an industrial application where the cure has to be controlled far more accurately, because you have massive loads on it, and you will have re-bar in the slab then you need DPM to help control the cure.

Entai · 30 Jun 2017 at 09:39

One thing I would say is why a concrete base at all ????

Seems huge overkill for a log cabin or garden shed.

We had several sheds, greenhouses and a cabin in my parents back garden, and all were laid on paving slabs on a sharp sand base.

None had any issues for over 20 years.

Hedge · 30 Jun 2017 at 13:05

Do you mind adding photos of finished job as I need similar in my garden. Thanks

snappyfish · 30 Jun 2017 at 19:26

Entai said:
One thing I would say is why a concrete base at all ????

Seems huge overkill for a log cabin or garden shed.

We had several sheds, greenhouses and a cabin in my parents back garden, and all were laid on paving slabs on a sharp sand base.

None had any issues for over 20 years.

Becuase 90% of the log cabins (sheds) I see have concrete bases, it's also recommended every where.

snappyfish · 30 Jun 2017 at 19:28

Hedge said:
Do you mind adding photos of finished job as I need similar in my garden. Thanks

Can do, not arriving until sometime mid-July, then will build when having time shortly after.

snappyfish · 26 Jun 2018 at 21:37

Freya13 said:
I got a garden room built recently, it's great as I have literally transformed it into an office for me and my husband. I got Bakers Timber to do it, and I am truly impressed by their work.

Seem them. Nice work on You Tube.

I thought I was clever and got someone to do concrete, and someone else to build it as I didn't have time! End result was around 6k then I had to take whole think down and rebuild it and build a sub frame as concrete was 100mm to 200mm to wide.

Lopéz · 27 Jun 2018 at 06:07

Entai said:
One thing I would say is why a concrete base at all ????

Seems huge overkill for a log cabin or garden shed.

We had several sheds, greenhouses and a cabin in my parents back garden, and all were laid on paving slabs on a sharp sand base.

None had any issues for over 20 years.

5m x 4.4m is pretty big for a paving slab base.

BurningHorizons · 27 Jun 2018 at 07:29

It seems like a decent price. Just make sure it is 100% level - no water run-off angle like a patio. Also consider that the weight of a cabin is around the outside, not in the middle. Their weight distribution is not like sheds.

Entai · 27 Jun 2018 at 12:42

Lopéz said:
5m x 4.4m is pretty big for a paving slab base.

One of their sheds was 12m x 8m, and three of the greenhouses were 20m x 10m and all on paving slabs.

Never had any issues.

Lopéz · 27 Jun 2018 at 13:56

Three 20m x 10m greenhouses? 20m is the length of two buses, what were they growing? How big was this garden?!

Entai · 27 Jun 2018 at 14:57

Lopéz said:
Three 20m x 10m greenhouses? 20m is the length of two buses, what were they growing? How big was this garden?!

Whole plot was just under 8 acres, but a lot was small woodland, and pasture/meadow land, I guess about 1 to 2 acres was a small garden nursery, mum ran, had the three big green houses and about 5 other smaller ones, along with some laid out lawns and borders showcasing plants.

PlacidCasual · 27 Jun 2018 at 19:15

Ok last year I poured 20m2 150mm deep concrete pad. It cost £600ish in concrete. 4 bags of hardcore was about £200. Mini digger £400 for a week (only 1 day work for pad) and the wood for shuttering £40. £1000 -£1200 doesn’t sound too bad for someone to do it even acknowledging they’ll get better rates on everything

Flibster · 27 Jun 2018 at 22:48

Did 4.5m by 3m ourselves recently, hired an mains electric mixer (toolhire iirc) for under £50 for a week including delivery and pickup. Only actually used it for 2 days then had them pick it up again. MANY trips in a knackered mondeo estate to load up on ballast and cement as nowhere could deliver for the next few days which was a pain. Few bits of wood for the frame and levelling.

Actually wasn't that difficult in the end. Just a lot of lifting and some sore muscles the next day.

Abyss · 28 Jun 2018 at 13:38

I'd agree there is some over engineering going on here.

All of the holiday parks with huge 2-3 bedroom log cabins I've been to are just sat on breeze blocks / paving slabs. A concrete slab with rebar and a DPM is overkill for most ground conditions.

I also wouldn't want the cost of getting concrete pumped in.

One solution I have been looking at is ground screws. Still overkill but no mess, removable and quick:
https://stop-digging.co.uk/
https://www.groundscrewcentre.co.uk

For a 5.5mx4m cabin you'd probably want 16-20 ground screws so about £600 plus some weed membrane and pea shingle to finish the area off.

snappyfish · 10 Jul 2018 at 12:23

Abyss said:
I'd agree there is some over engineering going on here.

All of the holiday parks with huge 2-3 bedroom log cabins I've been to are just sat on breeze blocks / paving slabs. A concrete slab with rebar and a DPM is overkill for most ground conditions.

I also wouldn't want the cost of getting concrete pumped in.

One solution I have been looking at is ground screws. Still overkill but no mess, removable and quick:
https://stop-digging.co.uk/
https://www.groundscrewcentre.co.uk

For a 5.5mx4m cabin you'd probably want 16-20 ground screws so about £600 plus some weed membrane and pea shingle to finish the area off.

Great idea this, wish I has done that. Builders made concrete 200mm to wide all round, water run under cabin. Tried cutting concrete back didn't work, took whole thing down and now on paving blocks on subframe.

Cost a fortune, time and effort. Tradesmen were awful as I took there advice. Still not great! But lesson learned!