Can I cut a notch out of a wall joist - partition wall

Hello,

I'm wanting to install a B&W in wall speaker in to one of my spare bedrooms.

I've received the speaker today and have been marking out the location.

Where I want to locate the centre speaker is a wooden bean which will protrude about 20mm where I want the speaker to go.

I know some people are going to save shuffle it across slightly but I really want it to be exactly centre of the wall along with the television so moving it isn't really an option.

The wall is just a divider wall between two bedrooms and is basically a timber frame with plaster board on each side. It doesn't support any weight (I don't think :confused:)

Anyone give me a little info / pointers? Would I be ok to cut a notch out to fit the speaker where I want it?

Any help is greatly appreciated.

Thanks
Mark :smashin:
 

Geps

Well-known Member
Notch out to what depth? Or do you mean all the way through?

The best way would be to take it out and the support the remaining timber with horizontal noggins above and below fixed the the studs either side.
 
Thanks for the reply.

I'm not sure how deep the joists go yet as the wall is 85mm deep but would need the whole depth in order to get the speaker in.

Not sure if I can get in to add an cross beams etc.

From googling around the wall supports no load as theres nothing below it downstairs so its basically there just to support the plasterboard.
 

J-a-m-e-s_7

Active Member
Hi, there are a number of things you could do but most of them will involve making good e.g. patching back in what you remove. If its just a stud wall and it is only supporting the weight of itself no units or heavy things attached to it then yes technically you could do what you are saying but i would only advise this if you have substantual studs as it will create a weak point. However, i would be tempted to add some noggins or and extra stuf if it were me.

For example, if you end up cutting through the stud completely although you say you only need 20mm then say if your studs are 600mm centres the effectively you've got a gap of 1200mm of unsupported plasterboard which if you ever fell into it or knocked it would be very weak and you'd go right through.

You say the wall is 85mm what size timber was used for the studs? this seems very thin if that includes plasterboard and a skim on both sides? Usually there closer to min of 100mm+. I think regs quote notching allowed up to 25% of the width in bearing wall studs and up to 40% in non bearing partitions but dont quote me on that so you should be ok to go a head. I just thought i'd mention about add extra support so i have covered all avenues.

You could also move the stud down a bit to allow for the speaker or sister it with another stud on the other side to support the part you cut out. But this will involve some of the plasterboard being removed to allow access to add the noggins/new stud. Seems a lot of work for something so small i know, although i share you desire for having everything centre etc equal and so on lol a bit ocd like that. I would personally add so reinforcement just for safe measure.

James
 
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Many thanks for the great reply.

I've only got some small pilot holes at the moment so can't fully see the size of the timber used to build the frame.

The batons (studs) are 18 inches apart, so 450mm I make that??

I've cut out two holes where the brush plates are for the cables for the TV and measured through to the rear of the other wall to see if my in wall speaker would fit and getting 85mm from the back of the plasterboard to the front of the other side :-s

To add any real support would require me taking out a fair bit of the plasterboard out which I really didn't want to do. But if I have the centre speaker off centre it'll bug me all the time its there!

The only other thing I could do which I've just thought of is to put the speaker off centre between the batons and then make a false speaker grill for the front which is slightly larger than the speaker and centre it up? (If that makes sense?)
 

J-a-m-e-s_7

Active Member
No problem at all. Generally stud walls can be built to any depth required, depending on the space available. The most common stud measurements are 63x38 in new builds/rennovation work, 75x50 and 100x50 are more common though. 450mm centres is good news though it means the wall has more studs and therefore stronger. From what you have said i think the studs will be 75x50mm (3x2") so with the two layers of p.b. and then the skim 2-3mm will give you just over the 100mm which is perfectly fine. So this also helps the fact that you only want to notch out one stud as the rest of the wall will be more than strong enough for what you want.

I would just go a head with notching it in this case and save yourself the hassle i was just worried before at the thickness of the wall as it has been known for people to throw up 50x50mm stud walls which can be extremly flimsy. I can't see any further problems arising. Btw did you get the timber you required ?
 
Thanks James.

I've just got the problem of trying to cut a notch out of some 75mm deep wood now lol!

I've not ordered it yet mate although it is for this room eventually. It'll take me a while to get started as I go on holiday on Thursday for 3 weeks and then back to my parents for Christmas so it won't be until the New Year before I order it.

Any recommendations for notching the wood out? Saw 20mm in top and bottom and chisel it out?

Many thanks
Mark
 

J-a-m-e-s_7

Active Member
lol well good luck with the project im intrigued as to what you are doing. Yeah probably your best option make sure you have a nice sharp chisel it will make all the difference. You may find it hard to saw the top and botton areas tho due to there being plasterboard on one side so go as far as you can without pushing through the other side go nice and slow and just use the front teeth on the saw as close as you can get to the back of the plasterboard then chisel out that section and use your chisel to finish off and clean up and high areas.

Regards
James
 
Thanks James

I might cut the plasterboard later and actually see what I'm facing :-S

Many thanks for your replies mate.

Mark
 

Geps

Well-known Member
Where abouts in Birmingham are you? You might be able to borrow my Bosch multitool as it has a plunge cut attachment that would help.
 
Thanks Geps,

I've installed it now :) just below where I've cut out is a cross member so any worries about compromising the strength of the wall have gone :rolleyes:

It seems nice and strong to me :thumbsup:
 

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