Office within factory

[johnfarris]

I am going to build a office within my new factory unit. I am not sure what to use CLS or 4 x2 . I am going to plasterboard the walls inside & out. Also I would like to put a flat roof on that will take anyone's weight who got on it.
Thinking of lining with OSB

What size timbers would be best for the walls, and what size would I need to use to span the distance & take the weight for the roof?


What would the forum recommend?

Thanks in advance

 

[RobinBHM]

I think 4 x 2 is a bit small for the roof span, you may want to go to 6 x 2.

I tend to use regularised studwork 47 x 95 finish for walls. Id be tempted to screw on 18mm osb before the plasterboard. Makes a solid wall and easy for any wall fixings.

 

[jimmy_s]

I would just use 89mm CLS for the wall timber frame and use OSB or Ply sheets fixed to the outer face - use the plywood to keep the timber frames square. Using the old rule of thumb for floor joints (if you want to be able to walk on it or perhaps store stuff over it) then a 6" deep joist should do.

 

[johnfarris]

I think 4 x 2 is a bit small for the roof span, you may want to go to 6 x 2.

I tend to use regularised studwork 47 x 95 finish for walls. Id be tempted to screw on 18mm osb before the plasterboard. Makes a solid wall and easy for any wall fixings.

Hi
thanks for replying. Is this what your refering to?

http://www.jewson.co.uk/timber/carcassi ... 7-x-100mm/

 

[johnfarris]

I would just use 89mm CLS for the wall timber frame and use OSB or Ply sheets fixed to the outer face - use the plywood to keep the timber frames square. Using the old rule of thumb for floor joints (if you want to be able to walk on it or perhaps store stuff over it) then a 6" deep joist should do.

Hello, Giving it more thought I am thinking if that, by lining with OSB or maybe a shuttering ply depending what's cheaper, I would get away with CLS 50 x 100mm

 

[jimmy_s]

I would think that would be fine.

 

[johnfarris]

I would think that would be fine.

Thanks
How would you support ceiling joists were they touch the wall ?

 

[jimmy_s]

The existing wall I take it? - do you know what its made from?

 

[johnfarris]

Yes existing and its made of brick. I was thinking timber bolted to wall with joist hangers nail on to it. Or may be notching timbers into timber plate, not something I have done before

Also noticed with the ceiling joists you can get different grades , doing a quick Google search brings up c16

Not sure what size I would use for timber bolted onto wall?

 

[carlb40]

As said 4x2 for the walls, 6x2 for the roof/ceiling and 6x2 bolted to the brick wall would be fine to use as a support for the timbers with hangers. Or if the brickwork is level and you can see the joints? You can get hangers that fit into the brick wall.

 

[johnfarris]

As said 4x2 for the walls, 6x2 for the roof/ceiling and 6x2 bolted to the brick wall would be fine to use as a support for the timbers with hangers. Or if the brickwork is level and you can see the joints? You can get hangers that fit into the brick wall.

Hello
when you say 4 x 2 are you referring to CLS or Kiln Dried C16 Treated Regularised Carcassing 47 x 100mm

 

[johnfarris]

Would these
http://www.screwfix.com/p/simpson-stron ... f-4/83833#

work with

http://www.jewson.co.uk/timber/carcassi ... 7-x-150mm/

When using anchor bolts what is the recommended spacing requirement when bolting timber to the wall for the requirement above?
Also what size anchor bolts would I need to use?

thanks

 

[RobinBHM]

Hi John,

To clarify 4 x 2 in the past used to be just sawn timber and not very accurate. Regularised is machined to an exact section making it easier to construct studwork walls flush. Different suppliers may have different sizes so its best to use the same supplier.

CLS is also regularised but is a Canadian standard.

Both are whitewood which is spruce.

Various grades are available but a lot of builders merchants stock C16 stress graded timber which is pressure treated as a stock item.

Joist hangers are available in 45mm/47mm width for regularised and 50mm for sawn. The ones you have linked should be fine. I believe they can be used face fixed onto your wall plate although you can also bend over the top as well (a builder / chippie may confirm).

The wall plate can be fitted with concrete screws or rawl bolts.

You will need 3.75mm x 30mm long square twist nails for the joist hangers. Dont use screws!

 

[johnfarris]

Hi John,

To clarify 4 x 2 in the past used to be just sawn timber and not very accurate. Regularised is machined to an exact section making it easier to construct studwork walls flush. Different suppliers may have different sizes so its best to use the same supplier.

CLS is also regularised but is a Canadian standard.

Both are whitewood which is spruce.

Various grades are available but a lot of builders merchants stock C16 stress graded timber which is pressure treated as a stock item.

Joist hangers are available in 45mm/47mm width for regularised and 50mm for sawn. The ones you have linked should be fine. I believe they can be used face fixed onto your wall plate although you can also bend over the top as well (a builder / chippie may confirm).

The wall plate can be fitted with concrete screws or rawl bolts.

You will need 3.75mm x 30mm long square twist nails for the joist hangers. Dont use screws!

Thank you Sir your a top man. So is regularised 4 x 2 better its equivalent CLS?

Also having trouble finding the info on how to calculate the length & diameter of anchor bolt needed to bolt timber to wall, any thoughts?

On a separate note I have been looking at shuttering ply & plasterboard, why is shutering ply 20mm wider & 40mm longer than plaster board?

 

[tim burr]

On a separate note I have been looking at shuttering ply & plasterboard, why is shutering ply 20mm wider & 40mm longer than plaster board?

Metric v's imperial, 2440 x 1220 is 8ft x 4ft, I suppose they do plasterboard in 2400 x 1200 as it's the nearest round number in metric??

 

[RobinBHM]

Not a lot, but CLS tends to be 38mm x 89mm so a bit on the small size.

If you run the wall plates over the start of the stud wall then they will be supported at one end anyway.

M10 rawlbolts will be fine. Although a double staggered row of concrete screws would be fine too. Much depends on the brick hardness and soundness of wall.

Well spotted on the size! -plasterboard is metric width so you will need to trim the osb / ply to match

 

[johnfarris]

Not a lot, but CLS tends to be 38mm x 89mm so a bit on the small size.

If you run the wall plates over the start of the stud wall then they will be supported at one end anyway.

M10 rawlbolts will be fine. Although a double staggered row of concrete screws would be fine too. Much depends on the brick hardness and soundness of wall.

Well spotted on the size! -plasterboard is metric width so you will need to trim the osb / ply to match

Thanks again, what screws do you use for the regularised studwork? Also if i went for the a double staggered row of concrete screws what length would be best?

 

[RobinBHM]

Woodscrews, probably 5mm x 80 and maybe 5 x 100 for spiking (diagonal fixing for inline noggins).

Concrete screws prob 7.5 x 112 length. I buy them from leo fixings. The drill bit in the brick is critical, from memory I think 6.5mm dia.

 

[carlb40]

Hi John,

To clarify 4 x 2 in the past used to be just sawn timber and not very accurate. Regularised is machined to an exact section making it easier to construct studwork walls flush. Different suppliers may have different sizes so its best to use the same supplier.

CLS is also regularised but is a Canadian standard.

Both are whitewood which is spruce.

Various grades are available but a lot of builders merchants stock C16 stress graded timber which is pressure treated as a stock item.

Joist hangers are available in 45mm/47mm width for regularised and 50mm for sawn. The ones you have linked should be fine. I believe they can be used face fixed onto your wall plate although you can also bend over the top as well (a builder / chippie may confirm).

The wall plate can be fitted with concrete screws or rawl bolts.

You will need 3.75mm x 30mm long square twist nails for the joist hangers. Dont use screws!

Thank you Sir your a top man. So is regularised 4 x 2 better its equivalent CLS?

Also having trouble finding the info on how to calculate the length & diameter of anchor bolt needed to bolt timber to wall, any thoughts?

On a separate note I have been looking at shuttering ply & plasterboard, why is shutering ply 20mm wider & 40mm longer than plaster board?

That is normally specified by the architect/engineer at the drawing stage as they will work out the loadings.
The general rule of thumb for timber fixings is 2.5 x the thickness of the timber being fixed. So lets say a 50mm thick timber will require a fixing of 125mm or longer . I would suggest without going too over the top m12 bolts 150mm long.

 

[DiscoStu]

A mate of mine had this requirement for his industrial unit. He just bought a portacabin off eBay and stuck that in there. Works brilliantly. Just an idea