WHICH NAILS for wall plate and joist overlap?

buky · 03-03-2019 10:06am #1

Hello Folks,

doing a renovation and wall plate resting on block will be 3x4. Are spring nails otherwise known as express nails good for this? I presume bolting is overkill.
Also joists are 7x3. Nailing the overlap in centre is 6 inch nails ok or should something heavier be used.

Many thanks in advance.

Calahonda52 · 03-03-2019 11:15am

Whats the exposure like for the site?
what are you doing re straps?
How often are you putting the express nails, what diameter and length?

the_pen_turner · 03-03-2019 12:37pm

express nails are great for this.
use plenty of wall plate straps too

i bolt any overlapping joists together and bolt to the rafters. its more work but really ties everything together

a few long straps up onto the ceiling josts or rafters here and there is a good idea too. even better if there is a runner

buky · 03-03-2019 2:17pm

thanks turner, what exactly are runners?

Cheers

the_pen_turner · 03-03-2019 2:22pm

buky wrote: »

thanks turner, what exactly are runners?

Cheers

Timber running along the top of the joists at 90 degrees . It ties it all together

Mahogany Gaspipe · 03-03-2019 8:19pm

Using a 4x3 as wallplate and express/spring nails is the incorrect arrangement for this detail.
4x3 is near impossible to straighten if warped; express/spring offer little or no shear strength.

The correct method is to use 4x1.5 (x2) wallplates.
Snap a chalkline and steel nail the first 4x1.5 to this line, this will (and is only to) ensure correct lateral set-out.
Eyeball and pack this first wallplate to set it straight in the horizontal plane.

Then wire nail the second 4x1.5 on top and strap down with galvoband every 1.5M, ensure that the galvoband extends down over the walls for at least two blocks either side.

Twisted galvostraps fixed to every third rafter, bolting is general not required.

the_pen_turner · 03-03-2019 8:44pm

Mahogany Gaspipe wrote: »

Using a 4x3 as wallplate and express/spring nails is the incorrect arrangement for this detail.
4x3 is near impossible to straighten if warped; express/spring offer little or no shear strength.

The correct method is to use 4x1.5 (x2) wallplates.
Snap a chalkline and steel nail the first 4x1.5 to this line, this will (and is only to) ensure correct lateral set-out.
Eyeball and pack this first wallplate to set it straight in the horizontal plane.

Then wire nail the second 4x1.5 on top and strap down with galvoband every 1.5M, ensure that the galvoband extends down over the walls for at least two blocks either side.

Twisted galvostraps fixed to every third rafter, bolting is general not required.

i think you need to find a new supplier for timebr if you cant get straight ones or ones that cant be esily straightened.

where are you getting your specs on sheer load. my googling is showing 1.1KN sheer for a 8 x 130 express nail in brick

hilti are claiming their nails are getting 1.15kn in concrete.

4x2 is handy for overlapping the joins and corners

Calahonda52 · 03-03-2019 8:59pm

MG:
re
The correct method is to use 4x1.5 (x2) wallplates.

Correct by whom?

Mahogany Gaspipe · 03-03-2019 9:04pm

the_pen_turner wrote: »

i think you need to find a new supplier for timebr if you cant get straight ones or ones that cant be esily straightened.

where are you getting your specs on sheer load. my googling is showing 1.1KN sheer for a 8 x 130 express nail in brick

hilti are claiming their nails are getting 1.15kn in concrete.

4x2 is handy for overlapping the joins and corners

Nothing to do with supply chain tbh.
If a roof list calls for 10 lengths of 4x3 and if they are left on site for any amount of time its unlikely they will be straight by the time they are used, and that is also assuming the unlikely event that they were all straight delivered to site.

With all due respect quoting sheer loading specs is not applicable here, at least not without demonstrating robust qualification.
What is the max sheer load that the single cavity closer laid on twin leaf blockwork can resist? How are you factoring hiltis numbers into that arrangement. From what dimension from the concrete/brickwork junction are those numbers generated; 75mm? Doubtful.

Also, using 4x1.5 is not for handiness sake. It is the correct method employed to achieve structural and aesthetic requirements.

the_pen_turner · 03-03-2019 9:13pm

Mahogany Gaspipe wrote: »

Nothing to do with supply chain tbh.
If a roof list calls for 10 lengths of 4x3 and if they are left on site for any amount of time its unlikely they will be straight by the time they are used, and that is also assuming the unlikely event that they were all straight delivered to site.

With all due respect quoting sheer loading specs is not applicable here, at least not without demonstrating robust qualification.
What is the max sheer load that the single cavity closer laid on twin leaf blockwork can resist? How are you factoring hiltis numbers into that arrangement. From what dimension from the concrete/brickwork junction are those numbers generated; 75mm? Doubtful.

Also, using 4x1.5 is not for handiness sake. It is the correct method employed to achieve structural and aesthetic requirements.

why have oyu timber sitting around before being used. any time i have done a roof or been on a site with someone else doing it , all the timber was delivered on or the day before the roofers were on site.

im not saying those sheer load rating mean anything. you claimed express anchors have no sheer value . i put up an example where they have a higher sheer value than steel nails

i have never seen 4 x 1.5s used or speced on any drawing for a roof. i have a drawing here in front of me by an architect that has 100x 75mm on it

Mahogany Gaspipe · 03-03-2019 9:29pm

the_pen_turner wrote: »

why have oyu timber sitting around before being used. any time i have done a roof or been on a site with someone else doing it , all the timber was delivered on or the day before the roofers were on site.

im not saying those sheer load rating mean anything. you claimed express anchors have no sheer value . i put up an example where they have a higher sheer value than steel nails

i have never seen 4 x 1.5s used or speced on any drawing for a roof. i have a drawing here in front of me by an architect that has 100x 75mm on it

A roof lot may be onsite for a few days, besides it will have been in a yard prior to delivery anyhow.

I didn't suggest that they have zero sheer strength just not what is required in this arrangement.
I did also make the point that the use of steel nail was only to facilitate positioning of the wallplate, I actually use spring nails for this also, both are really good to fix the wallplate in the lateral plane but still allow subsequent sighting, packing and fixing to the correct horizontal position.

You wont see 4x1.5 (x2)specified; only 100x75 as you point out.
100x75 is the finished dimension of the wallplate and its certainly required to transfer the roof loads but using a build-up of (2x) 100x35 will make achieving a first class finish much easier.
Give it a go and let me know what you think.

Mahogany Gaspipe · 03-03-2019 9:33pm

Calahonda52 wrote: »

MG:
re
The correct method is to use 4x1.5 (x2) wallplates.

Correct by whom?

This is a carpentry workmanship issue so I would respectively ask you not to get your Arch tect/Structural Eng knickers in a twist:D

sydthebeat · 03-03-2019 9:34pm

Much more possibility of a 4 X 1.5 twisting on site than a 4 X 3

the_pen_turner · 03-03-2019 9:39pm

not sure what way it will make it easier to achieve a top class finish.
it would be handier on corners etc but other than that what diference does it make

if you get a name for only accepting good straight timeber and sending back anything twisted , then they will only send out good ones. most of the time at least

Mahogany Gaspipe · 03-03-2019 9:39pm

sydthebeat wrote: »

Much more possibility of a 4 X 1.5 twisting on site than a 4 X 3

Yes but also much, much more possibility of straightening it.

In addition to this ordering 4x1.5 instead of 4x3 ensures delivery of twice the amount of lengths of timber which means the carpenter can be much more discerning in selecting which timbers to use.

Mahogany Gaspipe · 03-03-2019 9:45pm

the_pen_turner wrote: »

not sure what way it will make it easier to achieve a top class finish.
it would be handier on corners etc but other than that what diference does it make

if you get a name for only accepting good straight timeber and sending back anything twisted , then they will only send out good ones. most of the time at least

Well I'm going to leave it there, whatever works for you mate.

the_pen_turner · 03-03-2019 9:46pm

Mahogany Gaspipe wrote: »

Well I'm going to leave it there, whatever works for you mate.

explain the benifits

Calahonda52 · 03-03-2019 10:12pm

MG: the good news is that I have you on my ignore list, I think you were the second one on.
The bad news is that when folk here quote your insights....

You are the one who started the chat about shear, how is it suddenly not relevant?

You then told us that the correct way is blah blah blah

Why not share the basis of the correct way?

Most here share and learn

the_pen_turner · 03-03-2019 10:14pm

if anyone else is reading this.
dont use galvoband to hold down a wallplate. use the proper straps

Mahogany Gaspipe · 03-03-2019 10:59pm

Calahonda52 wrote: »

MG: the good news is that I have you on my ignore list, I think you were the second one on.
The bad news is that when folk here quote your insights....

You are the one who started the chat about shear, how is it suddenly not relevant?

You then told us that the correct way is blah blah blah

Why not share the basis of the correct way?

Most here share and learn

I'm not following the good/bad thing tbh?

I never said shear was not relevant. I said quoting shear resisting values which do not consider the specifics of this of this type of construction detail is a pointless exercise and I'd go further and say it may be a dangerous one as it may lead to erroneous results and incorrect conclusions.

Anyway, to the best practice.
The wallplate has to be set out to two critical positions: laterally which establishes the span/run; and horizontally which in conjunction with the ridge position establishes the rise.
It is crucial that the wallplate position is set right, all subsequent setting out of the roof is taken from it so it pays to focus attention in ensuring this.
OA wallplate dimension is generally 100mmx75mm this size will satisfactorily transfer the roof loads from the feet of the rafters and transfer them over the blockwork.
Generally the issue is that a timber with a larger cross section is much more likely to be affected by post felling defects, warping, twisting, bowing etc.... than timber of a smaller cross section. And those defects have to be rectified and are much easier to deal with in smaller section timbers.

Using 2x 100mm x 37mm wallplates allows setting of the wallplate to be broken into two steps; the reduced cross section means that the first wallplate can be pulled and pined to the chalked span line with relative ease and without any care of the horizontal level which can be subsequently sighted, packed and set to level in the second step.
To position a larger cross sectioned 100mm x 75mm timber with similar accuracy is not possible, well by me at least, if anyone else can more power to them.

the_pen_turner · 03-03-2019 11:11pm

i can push /pull a 4x3 wallplate to a line with 1 hand while drilling with the other.

you must be dealing with very bad blocklayers. the last 2 houses i was involved with roofing , i was a sub contracter. he used a laser level to check before we started and couldnt find anywhere that was out of level. shockingly level. i dont know how they got them so good but they were perfect.

Metric Tensor · 04-03-2019 11:29am

I remember in my early days of looking at drawings/specs of cut roofs (when I was in short engineering trousers so to speak) seeing 2 No. 4 x 1.5s exactly as Mahogany Gaspipe has described. It's definitely an old school way of doing it down my end of the country, which seems to have gotten lost somewhere in the last 10-15 years.

Many good building practices were "lost" in the boom times in favour of quicker techniques - I must confess in this case that I haven't done any structural analysis or given serious thought to which is better! But to be fair to Mahogany he's not "out on his own" in terms of this detail. What area of the country do you operate in Mahogany? You'd be surprised at the differences I've seen from one side to the other!

Calahonda52 · 04-03-2019 7:31pm

Metric Tensor wrote: »

I remember in my early days of looking at drawings/specs of cut roofs (when I was in short engineering trousers so to speak) seeing 2 No. 4 x 1.5s exactly as Mahogany Gaspipe has described. It's definitely an old school way of doing it down my end of the country, which seems to have gotten lost somewhere in the last 10-15 years.

Many good building practices were "lost" in the boom times in favour of quicker techniques - I must confess in this case that I haven't done any structural analysis or given serious thought to which is better! But to be fair to Mahogany he's not "out on his own" in terms of this detail. What area of the country do you operate in Mahogany? You'd be surprised at the differences I've seen from one side to the other!

Nobody is arguing about the rights or wrong here: it was, at least for me a question about the correct detail approach, without supporting documentation

Mahogany Gaspipe · 04-03-2019 10:39pm

Metric Tensor wrote: »

I remember in my early days of looking at drawings/specs of cut roofs (when I was in short engineering trousers so to speak) seeing 2 No. 4 x 1.5s exactly as Mahogany Gaspipe has described. It's definitely an old school way of doing it down my end of the country, which seems to have gotten lost somewhere in the last 10-15 years.

Many good building practices were "lost" in the boom times in favour of quicker techniques - I must confess in this case that I haven't done any structural analysis or given serious thought to which is better! But to be fair to Mahogany he's not "out on his own" in terms of this detail. What area of the country do you operate in Mahogany? You'd be surprised at the differences I've seen from one side to the other!

Well I served my apprenticeship in Galway and its the way I was taught.

I personally wouldn't put too much thought into which arrangement is better structurally. Once either arrangement is galvobanded over the blockwork correctly both would perform satisfactorily. Aside: A timber wallplate isn't, and should never be, the primary element called upon to resist lateral spreading of the roof; that resistance comes from either triangulation from ceiling joists, concrete ring beam or structural ridge.

It is really for craftsmanship I prefer laying the wallplates in a 2x build-up.

Metric Tensor · 04-03-2019 10:51pm

Mahogany Gaspipe wrote: »

Well I served my apprenticeship in Galway and its the way I was taught.

I personally wouldn't put too much thought into which arrangement is better structurally. Once either arrangement is galvobanded over the blockwork correctly both would perform satisfactorily. Aside: A timber wallplate isn't, and should never be, the primary element called upon to resist lateral spreading of the roof; that resistance comes from either triangulation from ceiling joists, concrete ring beam or structural ridge.

It is really for craftsmanship I prefer laying the wallplates in a 2x build-up.

Snap on all counts!

With the possible exception the craftsmanship one - no-one has ever referred to any of my manual labour attempts as "craft" .... a different word that begins with cra... would be closer to the mark!!

buky · 07-03-2019 12:08am

thanks lads, so helpful.
the joist overlap at centre wall. 7x3 joists. Can I nail these?

Trebhygt · 06-05-2024 5:27pm

Is 2 4x2,s the way to go for wall plate rather than just one ?

sydthebeat · 07-05-2024 8:34am

https://www.boards.ie/discussion/comment/122103746#Comment_122103746

Why would you need a 4x4 wall plate?

One 4x3 will suffice.

4x2 is not good enough.

Do you need extra floor to ceiling height?

WHICH NAILS for wall plate and joist overlap?

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