Timber frame in flood zone- ideas?

[DragsterDriver]

Has anybody got any experience with building timber frame in flood zone 3?

I will need to be 1m off the ground

 

thanks 

[nod]

The construction type should t make any difference The foundations will be designed to cope with any flooding 

[saveasteading]

Not exactly, but have designed other buildings to allow a river to overflow underneath.

 

Build up to 1m in any material you fancy: brick/ concrete/ steel. Make a deck on it in concrete. Waterproof. Build timber house on top.

Some areas will want to allow the flood under the building, others allow enclosure.

 

Have you established that this is allowed? There is usually the 'exception' test to satisfy.

[DragsterDriver]

3 minutes ago, saveasteading said:

Not exactly, but have designed other buildings to allow a river to overflow underneath.

 

Build up to 1m in any material you fancy: brick/ concrete/ steel. Make a deck on it in concrete. Waterproof. Build timber house on top.

Some areas will want to allow the flood under the building, others allow enclosure.

 

Have you established that this is allowed? There is usually the 'exception' test to satisfy.

1m off floor and 300mm resilient, I’m thinking build it on sleeper brickwork or similar? Whether that’s block and beam Or something else? It’s not something I’ve ever considered tbh but I’ve had a big let down on a plot and the best available has planning but flood zone 3!

 

edit: it’s a replacement dwelling so a bit of leeway.

Edited May 19, 2021 by DragsterDriver

[saveasteading]

That explains it, then ie replacing another so no increased flooding risk.

Sleeper walls is probably fine, and is nice and simple.

Needs bracing in the other direction to avoid domino collapse.

Can look ugly or weird though, so a bit of thought on appearance too.

If using concrete planks or T beams, you will want to conceal the faces, but perhaps the house wall facing can do that.

 

You will need an Engineer to design the sleepers, and perhaps the beams, but will be easy and inexpensive.

Brief them that you prefer sleeper walls or you might end up with a fancy in-situ concrete structure.

 

[DragsterDriver]

1 hour ago, saveasteading said:

That explains it, then ie replacing another so no increased flooding risk.

Sleeper walls is probably fine, and is nice and simple.

Needs bracing in the other direction to avoid domino collapse.

Can look ugly or weird though, so a bit of thought on appearance too.

If using concrete planks or T beams, you will want to conceal the faces, but perhaps the house wall facing can do that.

 

You will need an Engineer to design the sleepers, and perhaps the beams, but will be easy and inexpensive.

Brief them that you prefer sleeper walls or you might end up with a fancy in-situ concrete structure.

 

thanks- my brain is saying block and beam raised but it would be nice to give a ‘floating’ effect (excuse the pun!)

[joe90]

[SteamyTea]

@joe90

You fitting a bilge pump?

[saveasteading]

Have done buildings on sleeper walls a few times, for reasons other than flood. Steep hillsides basically so some faces are high in the air.

If the authorities  are happy that the flood flows around your house, then you can infill, but promise not to use it as a handy storage area.

In case it really does flood it would be prudent to let it dry quickly, so let lots of air through. Yorkshire boarding? hit and miss.

The risk might be of animal life enjoying the sheltered area. Door/gate in it for maintenance?

 

If the council wants you to allow water under the building then perhaps they will still allow hit and miss boarding. For a more rugged effect you can use scaffold boards vertically, and stained. 

 

[joe90]

 

very little diagonal stability IMO.

 

(Sorry I am bored ?‍♂️)

 

in all seriousness sleeper walls sound the ticket, my foundations are in permanent wet ground and strip foundations.

[DragsterDriver]

It’s flood zone 3 but I don’t anticipate any really, but building 1m above doesn’t seem too bad. I’ve had a nightmare with a plot that I was all set to build on which I’ll post about at some point ?

[Mr Punter]

You will need either to elevate the building or have a sacrificial floor, like parking etc.  For 1m I would just elevate and where possible build up the surrounding ground levels.  Only 4 courses of blocks so no biggie.

[DragsterDriver]

9 hours ago, Mr Punter said:

You will need either to elevate the building or have a sacrificial floor, like parking etc.  For 1m I would just elevate and where possible build up the surrounding ground levels.  Only 4 courses of blocks so no biggie.

I do like the look of piles and using a Rsj frame to build off! I need to find a picture.

[DragsterDriver]

This is nearby  

[Mr Punter]

3 hours ago, DragsterDriver said:

This is nearby  

 

That looks like a haven for rats.  Unless the ground conditions dictate piled foundations, just do strip footings and raised beam and block.

[Russell griffiths]

1m isn’t really that high, the time you put down a couple of course of blocks then block n beam floor then 200mm of insulation and 80mm screed your up there. 

Alternatively I would have a row of Gabon baskets around the house site and back fill with 600mm of stone then an insulated raft.

 

i did mine on block n beam floor, but wish I had done the raft idea.  

[DragsterDriver]

1 hour ago, Russell griffiths said:

1m isn’t really that high, the time you put down a couple of course of blocks then block n beam floor then 200mm of insulation and 80mm screed your up there. 

Alternatively I would have a row of Gabon baskets around the house site and back fill with 600mm of stone then an insulated raft.

 

i did mine on block n beam floor, but wish I had done the raft idea.  

NOW WE’RE TALKING!!!!! Lovely house.

 

very nice- you did have lots of input into my recent disastererous venture  

 

Bloody love gaboon baskets.

[Russell griffiths]

Is that like a funny monkey but spelt differently 

[DragsterDriver]

17 hours ago, Russell griffiths said:

Is that like a funny monkey but spelt differently 

It’s the iPhone autocorrect ?

[DragsterDriver]

Screwpiles with a steel ringbeam looks handy!

[DragsterDriver]

Just to revisit this ive been asking around and consensus is that my idea sucks unless it’s high enough to walk underneath otherwise it’ll be full of shite. Fair do’s.

 

blockwork with some big galvanised grates set in it so any water could flow has been mooted.