roof truss joint to gabel end wall

[markblue777]

Hi All,
So we are in the process of buying our house through the right to buy scheme and we had our home buyers building survey done today. One point he did mention was that the block work in the loft needed re-pointing (as there are numerous holes and a couple of loose ish blocks) seems at the time of construction they decided to to finish it as nicely as they should have (built around 1984).

He advised that the blocks in the loft get re-pointed, he mentioned about a glue type resin that is commonly used anyone know the name of it?

and that we use the stainless steel strapping to attach the roof trusses to the face of the block work (the roof truss to the gable end roof)

are these the types of strapping he was talking about

http://www.toolstation.com/shop/Con...Metalwork/sd2797/Heavy+Duty+Strap+Bend/p43454

http://www.toolstation.com/shop/Con...etalwork/sd2797/Heavy+Duty+Twist+Strap/p61566

he said it is not a major issue but should be done just to ensure all is well.

Any advise on the best way to go about it.
Cheers

Mark

 

[blackrodd]

This strapping has been regs for some time, and I would say it IS a major issue if you would not like to see you're roof, or bits of it, on the deck, after a good old gale, as there is nothing holding the wall plates down apart from a few masonry nails, I have seen some on the news, roof gone in a gale, on the floor, nearly complete!
The "L" shaped straps are to hold the wall plate to the masonry, or blockwork every 2 mtrs centres.
The "Twisted" ties for holding the trusses to the masonry and the first and last trusses , as you say, against the wall.
Difficult to fit, at this finished stage, but you're insurance company will not be happy not seeing them in the event of a claim, and you know what they are like now for "wriggling".
Expamet do a light duty range of straps, easy to bend, which may help in bending small "bobs" for you're particular situation.
I would think it is on google, if you put in wall plate ties centres, etc.

Regards Rodders

 

[markblue777]

ok blackrodd thanks

I need to get up in the loft and have a little more of a look i will get a few pictures so it may be easier to say what needs what.

with the twisted ties do you just screw to the timber and blocks or nail? I would assume screwing would be stronger

Cheers
mark

 

[blackrodd]

You may find a chisel and hammer useful just to take a small bevel or chamfer to get the "twisty" ties to fit nice and neat, just where the "bendy" bit changes direction.
You will just have to do the best you can along the wall plate length, and never lose the surveyors report, when it is signed off!
Regards Rodders

Sorry, yes screw and plug the masonry and screws to the timber.

 

[markblue777]

From what i have read the gable end is attached to the roof trusses as shown in the attached picture.

From the info i got from the surveyor he said to tie the truss across the face of the block work. Could this be achieved via the light weight straps hammered around the truss to meet up with the block face?

Cheers

Mark

 

[markblue777]

You may find a chisel and hammer useful just to take a small bevel or chamfer to get the "twisty" ties to fit nice and neat, just where the "bendy" bit changes direction.
You will just have to do the best you can along the wall plate length, and never lose the surveyors report, when it is signed off!
Regards Rodders

I think i was not clear enough before he did not say about the wall plate not being fixed just that the end truss that meets the gable should be strapped to the block face

 

[blackrodd]

Oh dear! I forgot about those!
IIRC, They are 1200 long, for regs, I suggest you go up and have a butchers, you may be able to incorporate these with
You're pointing in. Regards Rodders

 

[markblue777]

Hey All,

Thought I would include some pictures so you can see more easily

Hopefully this can help identify what is needed.

The strapping to the trusses from the gable wall does exist (going to add a few more nails into them though)

The truss running along the gable wall (the one more to the top right of the picture not the brace in the middle) was what I was told to strap to the block face. Would 4 or so of the light weight straps do that, so i can bend them as needed to get a nice fixing across them (was going to use the 1600mm long ones)

As you can see pointing def needs redoing, or if anyone knows the resin product he said about that would be handy.

After repointing and adding the straps I think i will give it all a light render maybe that will help bind it all together a bit better and also help with the lack of cavity wall insulation


Any pointers is a big help.

Cheers
Mark

 

[lincs1963]

My observations are firstly this building passed the building regs of the day so don't get too hung up about bringing it up to todays regs.
However to comply with today's regs those straps aren't long enough. They shoud be fixed to three trusses through the face of the binder with 1 75mm x 4.5mm galvanised wire nail per truss, the way yours are done is incorrect as the strap is only connected to the binder. This is a very common way of fixinf straps and I must admit I have done many that way myself. Usually when tacked on ttp like yours only 35mm twist nails were used which Is not sufficient. Your straps should be no more than 2 metres apart in any direction.
Hope this is of interest, cheers, Neil.

 

[markblue777]

Hi Linc's,
Yeah I think I will strap the truss to the face of the block work the best that can be and put a few nails in to ensure the strapping that is there is at least a but more secured.

I cannot see an easy way of strapping the gable across 3 trusses so will run with what I can do. Unless you think it would be worth knocking a block out to put the straps in as needed and then resting the block

 

[markblue777]

Hi Linc's,
Yeah I think I will strap the truss to the face of the block work the best that can be and put a few nails in to ensure the strapping that is there is at least a but more secured.

I cannot see an easy way of strapping the gable across 3 trusses so will run with what I can do. Unless you think it would be worth knocking a block out to put the straps in as needed and then reseting the block

Cheers
Mark

 

[blackrodd]

The pics are very helpful.
As the previous poster said, the straps are 1200 long and should span 3 trusses, and "hook" behind the inner skin of blockwork.
As it will be very difficult at this stage, to fix the straps behind the thermalite block, I would, as you said,
fix to the block face with brown plugs and 50, or 60mm screws to about 3 fixing holes in the strap end,
And see if you can screw the wind brace (4"x 1") between the nails in a couple of places,to the trusses, and just make it as strong as you can.
To save confusion, The binder is the two 4"x 1"s that are fixed to the ceiling collars, that hold the trusses apart at 600 centres, ensuring the plaster board will fit centre on centre.
The wind braces are fixed in the shape of a W and should start and finish on the wall plate to stiffen
the truss under side, hopefully preventing lateral movement on each side.
The pointing in, on above ground thermalite block, should be a mortar mix of 6 to 1, without lime, as the usual 4 to 1 is too strong and will crack.
Wickes do a nice mortar sand that will be easy to fill in the absent pointing and gaps.
Their prices are pretty good too, without the usual price hassle.
Just "slot"the mortar mix in the vertical gap, from bottom to top, and smooth over, wetting with a brush in the usual, flicking motion, will help the dry blocks accept the mortar, and you may well find the finish mortar colour blends in very well with the existing.
HTH Regards Rodders

 

[markblue777]

Hi Rodders,

you said

I would, as you said,
fix to the block face with brown plugs and 50, or 60mm screws to about 3 fixing holes in the strap end,
And see if you can screw the wind brace (4"x 1") between the nails in a couple of places,to the trusses,

I was going to say

what do you mean with screwing the wind brace between the nails in relation to the picture. Do you mean:
A) a few screws through the strap into the brace
B) a few screws through the brace into the trusses
C) a few screws through strap to brace and screws brace to truss
D) screw through strap, through brace and into truss if possible (if not possible should i do a combination of the above 3 other options)

but after re-reading i understand your saying put the straps to span 3 joists on the face block work and fix to block work with 3 large screws instead of trying to get behind it to tighten up the lateral movement and then fitting through the brace and trusses as regs state now

the surveyor said about strapping the block work like the following (hope this helps explain)

Sorry, I am unsure on this and want to make sure I understand before just jumping in.

Thanks for pointing out the mix as well thats a helper for sure

Just out of interest how much would someone typically charge to do this type of job (re-point and re-enforce). Obviously need to get some money knocked of the house price for the work that needs doing and this is one of the jobs so would be nice to have an idea of what I should be look at.

Cheers
Mark

btw is the mix this

http://www.wickes.co.uk/Wickes-Ready-Mixed-Brick-Laying-Mortar-25kg/p/154139

 

[blackrodd]

Hello Mark, You showed, in the previous picture, the existing strap, nailed/fixed to the wind brace,
and what looked like the strap butted on the wall face,
Hence my comments in getting as many sensible screwed fixing as possible as in "D", as you say, a combination of all three.
I was under the impression this was the surveyors request. .
You're pic with red lining, shows he wants a strap each side if the "rung" of the gable ladder you can just make out.
The "rung's" sit flush with the top of the inside truss, sits on the blocks, and carries the soffit and the barge board rafter, that's outside.
If you were able to find a Expamet stockist, the lighter duty straps would be easier to bend and fiddle into some tighter placer, they do have the desired Agrement number that says they have been tested successfully,
You had better check, but I think 4 screws , drilled and plugged on the block face will suffice and screwed to the truss, as you have drawn
The Wickes mortar mix may not be 6 in 1 that is used for Thermalite block.
You can put lime with the mix, but it is dangerous stuff especially for eyes and throat and lungs!
Regarding the labour cost, whatever the daywork cost is I would guess and say 4, or 5 hours, get well boarded out to prevent
the ceiling boards from popping their nails!
.HTH Regards Rodders

 

[markblue777]

Hi,
The straps that are on the wind braces on instruction are I'm the wall. Not sure if they bend behind the block work or not though. But the bend is not just buttered in. I think I will get a couple more straps and add as described before and also re-enforce the existing.

I will try and get a hold of the expamet straps or something similar that will enable me to do what needs to be done in regards to bending them around.

Thanks for the info and help. Much appreciated.

 

[blackrodd]

Hello Mark, Glad to be of any assistance.
I hope you get on well you're job's list, and get the surveyor to"sign off" The work to you're roof area sometime soon,
Then You're Insurance company can't "wriggle", as the dirty dogs always seem to. Regards Rodders

 

[markblue777]

Good point I will ask if they will come back and sign off or if I need someone else to sign off.

Cheers
Mark