Concrete Barge on timber frame house

bambampop

Hi all, anyone know the best detail for putting a concrete barge on a timber frame house? i had heard a whisper that there's a product that comes in sections that is supported by the block leaf only and cantilevered over the timber leaf but i cant find anything on the internet. The engineer seems hapy that the TF could support a poured concrete barge but id be interested to take a look at that product if it exists

Thanks

Carlow52

My view is don't do it as there will be movement in the TF inner leaf which may be enough to cause cracking on the outside just where u don't need it

bambampop

aye, that concern was raised but unfortunately its a planning requirment to have em so im looking for the best possible option (settling issue aside) for an unfortunate situation. appreciate any more feedback

mickdw

There is a fiberglass overhead barge which fixes to other leaf only. Its quite a narrow barge at about 300mm wide whereas the concrete would be about 450 when cast across both leaves.
Pouring a concrete barge over just the outer leaf would also be a possibility and can look quite good although alittle narrower as above. In relation to movement between inner & outer, I dont see a problem if it is supported on the outer blockwork with the roof surface running across the inner leaf with the typical lead detail to side of raised barge. The lead will take any small amounts of movement.
Dont support it on the timber work, The timber will give alittle and will cause cracking and water problems

Carlow52

building:) on what mickdw has outlined, maybe a 225 on flat outer leaf

bambampop

@ mick: yeah that sounds good, It is contrary to what the engineer said but makes perfect sense to me. The outside edge of the barge is in line with the plaster finish so does that mean we could only use a barge the same width as the block leaf? or could it span over the cavity? would you have any links to that fibreglass product as i would still be keen to take a look at it.

@carlow: yeah that would be a good option but unsuitable here... now bear with me. the barge in question is on a higher section of roof with a room lower down to its side (the kitchen). The raft is already in so any increase in the size of the block leaf would mean a decrease in floor space to the kitchen and i dont think this would be a runner, it has already gotten smaller from what was originally planned.

Thanks guys

mickdw

I cant find anything on the fiberglass one. you say you are using a flush finish to the outside edge so a barge a little over 100mm would be too narrow really. I dont see why you couldnt cross the cavity to the timber leaf with the fiberglass version though as there would be no loading involved compared to the concrete ones. The fiberglass one is also waterproof so no worries re water coming down through the cap. If you were to go with this option, you could really use any width you wished (or at least any width you could get). The area underneath it could be boxed out in wood & then the lead work carried out as normal.
Loads of options but I just think the idea of the poured concrete supported on the timber structure is lunacy. It would be fine if there was a flexible joint at the masonry side but with a rigid connection between barge & the plastered wall, having it supported by a timber structure which by its nature it going to move is just wrong.
I cannot find a link to the fiberglass ones but Im sure a hardware store would help you out as they are quite common.

bambampop

fair enough, im gonna have to source one of these fibreglass ones it seems, thanks for the help.

keru

I know it has been a long time since you posted, but I have the same issue and was wondering how did you do the barge in the end? Did you find that fiber glass product? Assuming you have finished your build, any problem with the barge?
Thanks.