wallplate help for garage

[richard1600]

i am building a garage, 7m x 4m.

walls have been done, all lintels etc in, now was told to bed the wallplates ontop of mortar then screw them then use straps also. the roof is gonna be a slight pitch with board and felt.

my questions is., yesterday i bedded the wallplates on the mortar and they have not taken at all. is there something different i need to do with the mix to make the wood stick?? or is it just a layer?? the mortar has set nicely but the wood just lifts straight off.

thx.

 

[noseall]

It is normal and nothing to worry about.

The timber is not meant to adhere to the mortar but the mortar provides a flat even and level surface on which to seat the plate.

If you are building a cut roof (as opposed to trusses) it ia far more important to get the plates exactly parallel and level. Don't fix the plates down until you have achieved this.

 

[richard1600]

lol,,

thankgod for that,, i thought i had messed up and had to redo it all..

i spent along time getting it level. measured between sides and up and down, and used large level, and am happy its level ontop of the mortar bed.

so just screwing it down with wallplate screws and straps is whatholds it then.

what are the spacings of these fixings, i was told 1.6m for the straps, and 3 wallplate screws per 3m of length??

so that would be 6 screws either side and 4 straps either side ?

 

[noseall]

Holding down straps should be spaced at max 2m centres.

We don't bother with these until we have set the rafters out for fear of interference.

To stop the wall plates wandering around we lay a piece of timber across the plates, one at each end, then fix them once parallel.

If the span is unfeasibly large then we do put the straps on but with only one screw in the top. This at least helps counter spread whilst pitching the rafters up. Once the joists are on then fit the straps permanently using say 3 screws in the top (horizontal) and say 5 down the wall (vertical).

If you are confident you can space out the joists and rafters without them interfering with the straps and that the plates are exactly parallel, then fix the straps permanently.

 

[Chukka63]

mark ya wall plates out and then fix the straps and then place your trusses/joists and rafters.

 

[lostinfens]

I gave up bedding wallplates years ago, just made sure the top course was good & straight(as it should be ) & fixed directly onto it. Assuming that the top course of blocks/bricks is reasonable, then the bed is superfluous & can break up under the tender mercies of a Joiner.
This time of year particularly bedding a plate stops the job for that much longer for little return.

 

[noseall]

I gave up bedding wallplates years ago, just made sure the top course was good & straight(as it should be )

This is fine for stand alone structures.

About 95% of the work i do involves matching new wall plates to existing. Quite often is the case that the new plate may need bedding to reach the exiting plate height.

There is little to be gained in this scenario by spending extra time coursing up so that all works perfect. you are better off working the blocks so that you actually encourage a decent bed beneath the plate.

 

[richard1600]

thanks for all the help,,,

i have bedded it yesterday anyways, its covered up and in a couple of days will attach the wall plates,, anyone advise on how many screws to use, i got masonary screws and plugs spec for wallplates,, each side is 7m long, and i got 4x straps for each side also..

 

[lostinfens]

Wall plate bedding was always a Saturday morning skive on site, gave it the weekend to go off. Know what you mean as regards renovation etc, needs must and all that.
But as I said earlier, I found that it just wasn't necessary on new work, particularly on blockwork, just welt a few nails through & truss away. Stick the straps on later.

 

[Chukka63]

straps need spacing a max 2m apart.i just use wood screws into the plate and red plugs and 50mm screws in the masonary.in blockwork i put 1 screw in each block so every 225mm(3 courses) in brickwork.screw intot he joints,its easier.

 

[RedHerring]

straps need spacing a max 2m apart.i just use wood screws into the plate and red plugs and 50mm screws in the masonary.in blockwork i put 1 screw in each block so every 225mm(3 courses) in brickwork.screw intot he joints,its easier.

I have seen such specifications as 50mm minimum length of fixing into masonry and fixing in the lowest 150mm of strap.
Is this subject to BC or is just a 'Best Practice'?

 

[noseall]

straps need spacing a max 2m apart.i just use wood screws into the plate and red plugs and 50mm screws in the masonary.in blockwork i put 1 screw in each block so every 225mm(3 courses) in brickwork.screw intot he joints,its easier.

isn't this subject to BC or is just a 'Best Practice'?

Straps are part of the inspection process and must be fitted.

They are rarely measured unless the spacings appear unfeasibly large.

The same applies to both floor and rafter restraint straps. These too must not exceed 2m centres and must cross three rafters or joists and must include noggins between.

 

[Chukka63]

makes me laugh when you get a window/door over 2m wide hehe.

currently doing a loft conversion,no planning required.when we measured for the stair headroom,we were 25 mm tight,called the local BCO and explained if we moved the stairs to accomodate the height reg he said i could cut the roof insulation down enough to get the height required.lol

 

[richard1600]

guys,, thanks for all the advice, am a vehicle engineer by trade and not a builder, however given the right advice i am happy to do things myself...

can i ask about tolerences regards wall plate,,

ok so distances left hand wallplate and right hand are spot on, almost exact all along so happy with that, but how close do i need to be with regards to height? i am 221cm exact on both sides at one end of structure, 221cm high exact on both middle parts of structure. 221cm on front left and 222cm front right,

so its 221cm on both sides mostly all over, just front right is a cm more, (timber is not 100% true)

can someone tell me if this is ok to work to?

 

[Chukka63]

i wouldnt worry about that difference.