Knocking down a wall upsatairs

[marlb]

Hi all,

I am looking to knock down a wall upstairs. The house was originally extended out to the side, the full length of the house and the small 3rd bedroom was used as a corridor to the extension upstairs. I want to knock the old bedroom area into the landing and create a bigger, lighter area. I have been up in the attic and the only thing that the wall is supporting is the ceiling joists. What is the best way to support these once the wall is removed? I do not want anything showing below the ceiling like a boxed in beam. Can I use a wooden beam above the ceiling resting on a wall running at right angles to the one I want to knock down and use joist hangers to support the ceiling joists? Another problem is that the ceiling in this house actually goes into the attic by about 600mm. So I have a sloping look along each wall hence I will not be able to rest the other end of the beam on the original outside wall, can I attach the other end of the beam to the roof rafter. I wish I could show a drawing as it would explain better.

 

[Steve]

Your roof is like this?

The ceiling timbers rest on the roof timbers (probably fixed to the side). Whats to stop your new ceiling timber doing the same? You might have to double up the roof timber in question for support.

Let an expert comment though - im no expert!

I would get a structural surveyor to check it over too. You may not need any additional support.

 

[marlb]

Yes my roof is like that but the ceiling joists run in the opposite direction to wall that I want to knock down, So at present the ceiling joist run over the top of the wall and thus are partly supported by it.

 

[Newboy]

Just a quick check

Are you sure that the wall you want to demolish is not supporting anything else?

For example (in the loft) can you see any timbers running from a purlin (timber running at right angles to your rafters) down to the wall.

How old is the house and what type (semi/terrace/detached etc)

I have a feeling that you might be thinking of removing a section of the spine wall which is not a problem in itself but you do need to ensure that the loads currently taken by the wall are transferred correctly to other parts of the structure.

You need to think about how to temporarily support the ceiling structure BEFORE you take down the wall as well as the permant support afterwards

 

[marlb]

newboy,

No there are no timbers running from the purlins down to the wall. In fact the purlins are running right around the loft and do not have any timber running down to the ceiling joists. As the ceiling joist are only 3 x 2 they would not support much any way. The wall looks to be supporting 2 ceiling joists running at right angles to the wall. incidentally the extension to the side has been tied into the original roof and the ceiling joints on that look to be 12 x 2 and that side does have timber running from the purlins. I wish I could draw a diagram. Does any one know how to get a drawing onto this site??

 

[marlb]

Newboy,

sorry you also asked some other questions. The house is a 1940 semi with a full 2 storey side extension (added before we bought the house).
the upstairs rooms all go into the roof slightly. About 600mm into it!
I have had a good look in the attic and can see the roof rafters running down on all sides to the outside wall. The purlins supporting the rafters are attached only to the rafters. They do not look to be supported in any other way. I assumed that they were counteracting the weight of the roof and rafters in that they can not collapse as the weight of the roof etc is pushing against the 4 corners of the pulins.

 

[Newboy]

I think that you need some advice from an expert - a struct. surveyor as Setve suggested.

It may look as though the wall is providing limited support but it needs checking out before you think about removing it.

 

[marlb]

Ok will seek

Many Thanks

 

[Steve]

marlb it sounds very similar to our roof (also 1940s semi). The purlins (halfway up the roof) do not have other support, as far as i can see in ours, their weight load is taken by the corner rafters, which are quite a bit deeper. The purlins are deeper still, and they hang below the corner rafters which take their load, it looks quite unhealthy!

However i have a feeling, the purlins being one long length, most of the weight is taken by the party wall in the middle, but in your house with a full width extension this will not be the case as one side is heavier.