Loadbearing of plasterboard

[John]

I want to attach a 17" LCD TV to my bedroom wall which is straw filled plasterboard about 2 1/2" thick (built in 1992) The TV and bracket have a combined weight of 6.44KG (14.2 lbs) the bracket has a backplate measuring

45mm x 150mm, there are three fixing holes, two at the top with 25mm centres and one at the bottom which is 130mm lower and central. There are no studs near where the TV HAS to go. Will this end in disaster with the TV going South? I could spread the load by mounting a piece of sheet wood on the wall and screwing the bracket to that but I am trying to avoid that if possible. Will the PB take it or any other ideas anybody. Because of the straw inside I don't think butterfly toggles are an option.

TIA

John

[John]

I want to attach a 17" LCD TV to my bedroom wall which is straw filled plasterboard about 2 1/2" thick (built in 1992) The TV and bracket have a combined weight of 6.44KG (14.2 lbs, TV 5.4Kg Bracket 1.04Kg) the bracket has a backplate measuring

45mm x 150mm, there are three fixing holes, two at the top with 25mm centres and one at the bottom which is 130mm lower and central. The back TV will be approx 250mm from the wall. There are no studs near where the TV HAS to go. Will this end in disaster with the TV going South? I could spread the load by mounting a piece of sheet wood on the wall and screwing the bracket to that but I am trying to avoid that if possible. Will the PB take it or any other ideas anybody. Because of the straw inside I don't think butterfly toggles are an option.

TIA

John

[cj]

Hi John If you have what I think you have it was known as "Strawboard" and droped by our local builders in the early 80's . As for its physical strength FORGET IT we had trouble mounting dual sockets in it.(They pulled out after a few plugs were plugged in and out) We ended up putting 2x1 battens behind them. If it is this then your Plazma will be floor mounted in no time. You could try locating the vertical support studs and bracing externally behind the tv with 2x1 as the sheets we came across were in 3ft x 6ft panels with a 2x2 batten supporting them. I hope I am wrong in my assumption as the strawboard we had to deal with was very easily damaged (one guy actually fell through it,he slipped and crashed into the wall ) You say 1992 so it's most likely not the same .

HTH CJ

[Midge]

Not about to comment on your individual case John since a lot depends on the quality of materials, the precise type of plasterboard anchors you use, how far the weight is off the wall, how the weight is spread across the bracket, whether it might get knocked by anyone, how well the board is fixed and/or might flex etc etc.

What I will say is I have two problems in the last two houses where VERY heavy items - radiators and kitchen wall units respectively - have been put up by builders with plasterboard anchors, which have gradually torn through.

In both cases - my fix was to just take suitably sized blocks of timber, cut out windows in the plaster board, and plug/screw the timber direct to the masonry wall behind it such that the timber is nearly flush with the plasterboard surface, then skim over it with plaster or filler. Brackets are then screwed into a solid load bearing surface.

May be overkill, but then again, nothing I have ever put on a wall has ever come down again until I've wanted it to.

Midge.

[John]

I cannot do that as the other side of the wall is the staircase. The 'wall' is literally 2 1/2" thick and absolutely no masonary, breeze, etc. is part of it's make up I have done your solution in the kitchen where the PB is dotted and dabbed to a breeze block wall

Cheers

John

[Grunff]

So what is this plasterboard attached to, and how?

[John]

I don't know

, and how?

I don't know

All I know is the wall is filled with straw, ala the three little pigs!. We once had a leak in the en-suite shower and the other side of the wall bulged like you wouldn't believe. I replaced this section with a 'traditional' stud wall. I spoke to the builders (Perssimon sp?) and was told that the bathroom and en-suite walls were 'built of straw' for soundproofing purposes.

Cheers

Johnff

[Grunff]

Are you absolutely, 100% certain the wall is only 2.5" thick, from one side to the other?

If you are, and it really is made out of this strange material, then surely the only option you have is to provide some load bearing support by way of the floor or the ceiling joists.

There are many ways of doing this. For example, you could take a piece of timber, 10" wide and maybe 8' tall, and glue it to the wall (no-nails) with its bottom end resting on the floor. You then attach your bracket to this wood.

[John]

Absolutley certain, as the wall carries on out of the bedroom and is the return wall at the top of the stairs, Nothing in between apart from door architrave etc.

See my point about 'spreading the load' in my original question

?? It is only 6.44KG in total

I think this is a little OTT, and doesn't follow your idea above as the strain will be on the PB face not the joists!

Thi would not stop the bracket 'trying' to tear itself away from the wall, only stop it dropping vertically

You then attach

hanks for your input

John

[Grunff]

Is that 6kg held 2cm out from the wall? 20cm out from the wall? This makes a huge difference.

The vertical load, which admittedly isn't much, will be taken up by the floor. The horizontal load, tending to pull the board away from the wall, will be spread across the whole area of the board.

Yes, it would, because the tension in the board-glue-wall interface will be spread over a large area.

Good luck.

[Handy]

No, PB on it's own will not take it and it doesn't sound as if this partition can be strengthened without tearing it apart, in which case you may as well replace it with a stud wall.

[meow2222]

Indeed. I've had pb take more than 6kg, but it didnt last, the fixings pull through after a year or so. with 13cm between fixings, if your stickoutyness is say 26cm, then the PB sees 26/13 x 6 = 12kg lateral forces as well as 6kg downard force.

The other option is to add an upright piece of wood and attach your tv mount to that. This is say a 1.5"x2.5" planed piece of wood resting on the floor and fixed to the wall. Wickes sell CLS this size, which has rounded corners. The wood doesnt take all the forces, but will take most of it. 4 fixings to the PB should be enough keep it in place.

If instead you replace the whole wall, 2.5" - 2x.5" = 1.5", ouch. You'd need a lot of uprights at that size to get reasonable sound resistance.

NT

[meow2222]

When I first saw the title I thought it said 'loadbearing plasterboard'! Now I know some people cut corners, but...

NT

[Grumps]

You mean like this stuff

?

I don't think it's real plasterboard either. More like a thin skim over cardboard. Our house's internal walls (upstairs) are also of this construction. You can hang a picture, but forget anything more demanding. I bolted our wall mounted towel rail through the wall, the nuts emerging in the airing cupboard. Can you not hide any through-wall fixing with a picture etc?

[John]

Thats exactly the sh*te, I mean stuff

Upon further inspection and measuring if I place the TV bracket 6" to the left then it backs onto the airing cupboard so I am either going to use lonscrews (3 1/2 or 4") and no nails a piece of timber on the inside of the airing cupboard and screw into that, or long bolts and a predrilled pice of wood and bolt right through. Any thoughts or preferences, bearing in mind the screw holes in the bracket are only 6mm diameter and it isn't practical to them drill much bigger.

Cheers

John

[John]

Just as a side issue. On their website no matter which link I click I always get the Contact Us page. Anybody else?

Cheers

John

[Huge]

I hung a (CRT) TV on a bracket on a plasterboard & studding wall using cavity wall fixings a few years ago, and the wall started to bow outwards alarmingly.

I ended up fixing a piece of ply to the studs screwed through the plasterboard and mounting the TV on that. Looks OK when painted up.

[Adrian]

Not just you. Looks as if every link on their homepage goes to the contact page - including the one that (misleadingly) says 'sitemap'.

Every link - except the one that points to their website designers .

Way down in the source of the website it does say "Copyright to this/any designs will be transferred to Stramit open order." - which might mean that the website is a 'work in progress' - let's hope so !

Regards Adrian

[The Natural Philosopher]

The PB will take it IF you spread the load enough 61/2kg is not a huge load.

The problem with plasterboard is that the localised strength is not good enough for rawlplug/butterfly or any other sort of attachment.

You need to remove the section of plasterboard and put e.g. a sheet of MDF behind it and put it back, and either attach the MDF to the studs or glue it to the back of the board. Or in fact you can use a thin sheet of MDF to replace the board itself, and skim over it.

[Antix]

If you rely on the surface of the plasterboard, regardless of the distribution of force over the area, if you get another en-suite leak you might find the plasterboard disintegrate again and have to claim for a new TV on the insurance !

Ant.