Sagging lounge floor, wall above seems to be the issue...

[m4rcus]

Hi,

My house was built in the mid 80's. The lounge is approx 5.6x4m and spans from front to rear of the house. Above this room are the 1st and 3rd bedrooms. The dividing wall for these two rooms is built of what I think is the thermolite blockwork. The weight of this wall seems to be making the ceiling sag in the lounge. When I walk in the 1st or 3rd bedroom there is a little floor bounce.

The dividing wall runs the same direction as the floor joist. See side view.

Picture Title

• m4rcus
• 16 Oct 2012
• 1

There looks to be some minor cracking in the walls below the lowermost joist...

So here's the point of the post:

Who can I get in to take a look at the issue?
Could I just take down the wall and put up something lighter (plaster board) wall instead?

Cheers,

M

 

[maltaron]

It is quite normal to build 3" clinker block walls on floorboards. Looking at your drawing I would suspect that some ground floor walls have been removed. The floor joists would need to be at least 220x47 (9" x2") to span the 4 metres and I would be surprised it they are more than 7" x 2".

 

[m4rcus]

Thanks for the reply.

I can confirm that there never was a supporting wall as I've spoken to a couple of the neighbours with identical houses (apart from the sage). When I pulled up some of the boards in the upstaris bathroom I seem to remember that the joists were 2" wide and I swear they were 9" tall. I will check tonight and say.

So would you know what my options would be for a ceiling that does not sag?

M

 

[maltaron]

If the joists are 9 x 2 then they should be ok. If the neighbours have no sag then I suspect that one or more of your joists has failed. It will be necessary to carry out a proper inspection around the area of the wall to ascertain the problem.

 

[m4rcus]

I thought that might be the case. I was thinking of ripping down the ceiling to get rid of the horrible curved artexing... obviously I'm not qualified to say what's failed, what type of person would be?

Cheers,

Marc

 

[maltaron]

You will need to find a good carpenter or builder, preferably by recommendation. They should be capable of suggesting a solution but I think it will be obvious if there is a failure. I would suggest that it would be advisable to put some temporary props under the joists under the wall. It's surprising how much plasterboard can carry when spanning joists.

 

[m4rcus]

Could it also be due to the supporting wall having an issue? I'm thinking the issues I can see in the supporting walls (I'm at home taking a better look) might mean that joist has dropped a bit(!)

M

ps thanks for your help so far.

 

[tony1851]

It's surprising how much plasterboard can carry when spanning joists.

Eh?

 

[tony1851]

Have you looked into the cracking in the walls supporting the joist(s)?

 

[chickenlips]

Who can I get in to take a look at the issue?
Could I just take down the wall and put up something lighter (plaster board) wall instead?

Cheers,

M

To answer your question, yes you could take down the wall and put up a stud wall.

However there is still the issue of a saggy ceiling which probably means remedial work. A reputable builder should be able to advice you on what needs to be done.

 

[^woody^]

The floor wont ever spring back up if the wall is removed.

The actual cause could be a lot of things, and it may not even require the wall to be removed.

Would a builder be able to fully inspect the problem and come up with an appropriate, economic and efficient solution?

 

[m4rcus]

I'll get in a builder. I think in the mean time I'll make a few holes in the ceiling so I can poke a usb snake camera I borrowed into the void and take a look.

Thank you for the advice. I'll come back here and let you know what some builders have said.

 

[tony1851]

I'll get in a builder.

If you get in, say, 3 different builders to have a look, you will probably get 3 different explanations as to what has caused the sagging, and (probably) 3 different suggestions for remedial work, depending on how much work any particular builder wants.

Their advice may be free, but will it be impartial, informed and cost-effective?

There are many threads on this forum in which OPs have had remedial work done on a builder's advice, only to have the problem recur.

 

[m4rcus]

So would getting in a building inspector/surveyor be a better bet. Pay for proper advice then get a builder to do the work suggested?

M

 

[tony1851]

M.
Although there is a cost in getting a qualified professional to look at it with a view to designing a solution, this is usually the better option in the long run.

There are many competent builders out there who would understand what is causing the problem and could propose a solution, but who to trust?

At first glance, your case seems to suggest overloading of the joist immediately under the wall but I wouldn't feel sure this is the whole problem. The cracking in the walls at the ends of the joist might be cause for concern. It would be no good stiffening or replacing the joist if there is a problem in the wall at the bearings.

A surveyor, or an SE would probably be better able to advise than a builder.(Don't bother asking the Council's building inspector - they will only say 'get someone to look at it').