concrete pour for ufh

fatchance

Hi all,

My house is up, the roof is on and all our windows are in. The underfloor heating was laid last week and this saturday I intend pouring the finished floor. Weather won't be an issue cus it'll all be inside work but the huge drawback is getting the concrete in! No other way except truck to back door and wheelbarrow it in. The floor area is roughly 100msq so reckon 8m should do the job overall but I intend doing half the house this sat and the rest the following sat, don't want to bite of more than I can chew at once as it's a lot of lugging of concrete and help is scarce.

I've sheets of 1/2 inch ply split in two and plan to wheel the concrete on these to protect pipes, dispersing the weight. I've screeds down and I think I'm all set.

Have any of ye done this before? Any tips for me, things to watch out for? Do's or don'ts?

Any help would be appreciated. I know it's going to be alot of labour but it can't be helped, had no plumber organised when blocklayers landed!

Thanks all

byrner88

well if the problem is getting the concrete into the house you could always get a the concrete pumped into the house.

fatchance

Yeah but isn't that really expensive? I must enquire. The second half of the house will be the toughest/furtherist away from truck so I will definately suss out pump prices.

De_man

pump is the only way to go, it'll be a bit more expensive
but not too much more

Qwerty?

We got ours mixed on site, pumped and leveled for (i think) €6 a metre. All I had to do was supply sand and cement. Would be very wary of wheeling a borrow full of screed over UFH pipes.

fatchance

Qwerty? wrote:

We got ours mixed on site, pumped and leveled for (i think) €6 a metre. All I had to do was supply sand and cement. Would be very wary of wheeling a borrow full of screed over UFH pipes.

I must've rang dozen concrete crews who do/have done this before and they are all way to busy with bigger (and handier) jobs atm and didn't express much interest in doing job at all. I would have got someone to do it if I could but faced with no takers I've no choice. 6euro sounds great though, envious I am, much:p

I've PM'e you info of local (Athlone) screeder with a concrete pump.

Qwerty?

If you have a hall/corridor would you consider doing that the first day, using only buckets, then the following week, you can wheel down to the rooms, and tip borrows at doorways.

Don't be too envious, he keep me waiting weeks:rolleyes:

Be very careful with the steel float, my in laws screeder sliced one of the UFH pipes with it.

Salmon

Best of luck with your pour mate! Just poured a finished floor on my own place last week! It didt work out too bad after but the weather was a little dodgy for a while. At least you dont have to worry about the rain affecting you!! I like the idea that qwerty? had above. Whatever you do you must make sure that he UFH pipes are well protected! The concrete supplier will probably push to get it all done in a day, but if you could do it in stages all the better! Just one thing to remember is when the concrete is in you will need to rake it level and screed it off. Its nearly impossible to do this without standing on the pipes. Im not sure how much you can stand on those pipes because I didnt go with UFH but you should consider pouring in sections for this reason!

fatchance

Salmon wrote:

Best of luck with your pour mate! Just poured a finished floor on my own place last week! It didt work out too bad after but the weather was a little dodgy for a while.

Yeah, I was keeping an eye on your progress! I did upstairs my self with little bother, screeded it off and powerfloated it, looks well, but downstairs will be more labour intensive.

Out of curiousity I prices pump hire and the cheapest was midland pumps at 550e for six hours (shortest rental time), reckon I'd need them for two max.

Surprisingly enough the ufh pipes are pretty robust, toughened plastic inner and outter layer with aluminium inbetween so walking on them will be ok as insulation also helps to soften impact....a wheelbarrow full of concrete might be a different story but I'll be extra careful (and we have all said that before eh!!!!)

Saturdays the day.

yop

fatchance, what I did was I used boards nailed onto lathes that fitted in between the pipe runs, this meant that the lathes were taking the weight onto the subfloor and not the pipes,
If u have scaffolding boards put 1 or 2 side by side and naile about 3 laths cross ways on the boards.

We did out downstairs over 2 saturdays, get a good long level for laying the screed guides and bed them well in screed before laying them.
Make sure that the screed is not too wet but it maybe worth you while sprinkling a dash of water on the pile outside during 1/2 way though,

Put down heavy plastic underneath the pile outside to ensure that the water does not flow out of it,

Get plastic floats not steel ones, these are what are used for screeding

There is a cement additive for UFH also, ensure that the pipes take the concrete and don;t cause a gap around them, otherwise ur not pushing the heat up into the screed, could be a gimmick!

Make sure u have a good strong screed board, a 3*2 if u can, other wise it will rise over the screed you are pulling,

Good luck with it, expect to sweat!!

fatchance

Thanks Yop,

it'll be a good workout alright!!

What do you mean by "There is a cement additive for UFH ", I presume you just mean to tell the cement compamy what the load is for and to make sure it's a finished floor mix. Please explain.

Have screeds down and did use 3*2's lying flat, which should work out fine. Hired a laser lever for this job and done all the screeds I needed in a half day. The sub floor was slightly off level, deepest screed will be is 100mm and thinest is 60-70mm, which should work out perfect.