Arranging tongue and groove boards for garden gate

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On a tongue and groove ledge and brace garden gate , does it matter which side the orientation of the growth ring on the tongue and groove boards face?

Should the heartwood of the boards face the outside of the gate or inside or does it not matter?

My understanding is the outside of the board can expand and shrink at a different rate to the inside, leading to cupping. So if the heartwood is facing the outside of the gate the screws/fixings clamp the boards to the batten keeping it as straight as possible.

By the way both sides of the gate in my case are going to be exposed to the elements.

Any advise appreciated.
 

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that only looks like 7.5-8mm cladding you want the next size up at around 11mm
and you cant alternate as the groove is uneven and as said a "V" to the front
just select the best planks

{dont know where the itallics came from??]
 
that only looks like 7.5-8mm cladding you want the next size up at around 11mm
and you cant alternate as the groove is uneven and as said a "V" to the front
just select the best planks

{dont know where the itallics came from??]
sorry those arnt the correct boards in the pic - they were just to illustrate the growth rings. The boards I have are 20mm thick and have 'V' on both sides. what I was trying to ask is does it matter which side the orientation of the growth ring on the boards should go i.e. does the heartwood go on the outside or inside face of the gate.
 
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How about reversing alternate strips. Then if they cup in the usual way the edges are more likely to stay lined up?
 
OP. decorative T&G boards are machined with a chamfer at both sides on the outre face (the upper face on the photo you posted), That face goes outermost.

dont know where the itallics came from??]
Italy? ;)
 
OP. decorative T&G boards are machined with a chamfer at both sides on the outre face (the upper face on the photo you posted), That face goes outermost.


Italy? ;)

The boards I have have a chamfer on both sides. One side has a fractionally larger chamfer - see attache dpics. Does the large V go on the outside face and the braces fixed to the other side? If so then most of these boards will then have the heartwood (orientation of the growth rings) facing the inside and reading through the following link it discusses that the heartwood should be facing the outside face. https://www.secrets-of-shed-building.com/building_a_shed_door.html

Or maybe I'm just overthinking everything.

20220801_114338.jpg
20220801_114224.jpg
 
How noticeable is the V when you alternate them?
I can see the difference in the first picture but it may no be so noticeable in real life so long as the face of each side is level.
I can't see anything wrong with putting the smaller groove to the outside if you really want the heartwood on that side.
 
Well, the stuff in the second photo is a bit different to the first photo you posted!

Personally, I do think you are over thinking it. I also think that you've got the wrong end of the stick about what "heartwood" actually is (see below), and your understanding hasn't been helped by referencing an American web site where the author takes waney edge boards (which are pretty much always sawn hardwood) and where he clearly doesn't understand what heartwood is either (he actually means growth rings - yes, I did skim the site, that's 10 minutes I'll never get back):

Building a Shed Door 001.jpg


and then rips them down into straight planks:

Building a Shed Door 002.jpg



Building a Shed Door 002.jpg


which isn't the same material you are using. In hardwood, the heartwood is found between the pith at the very centre of the tree and the sapwood near the outer edges, just below a thin layer of cambium and the bark. The sapwood is the part of the tree which actually grows, whereas the heartwood, whilst not dead, is no longer growing. It provides strength to the structure of the tree:

Cross Section of a Tree.jpg


So to me talking about "putting the heartwood facing outwards" is just plain wrong, especially when you consider that when softwood is sawn it is invariably sawn T&T (or through and through), thus:

Through and Through Sawing.png



I chose that diagram to illustrate not only through and through sawing, but also the effect of moisture on grain orientation. The article in your link states:

'Cupping' can be mitigated by fixing the heartwood on the outside so that the screws/fixings clamp the board to the batten keeping it as straight as possible.

When what he actually means is growth rings.

If you look at the top edge of the timber, it's the growth rings which are the important bit, and if you want to go that way you'll need to orient your boards as above to get all the boards to cup outwards equally. But here's the rub - at college I was taught two alternative methods; in the first all the boards are set-up to cup outwards (or upwards), in the other method you alternate the boards so one cups outwards, the next inwards, the next outwards and so forth. Take your pick because in reality, it doesn't really matter how you do it.

One thing I would say is beware of taking what you read on an American website as gospel. The UK is a different country, sometimes with different processing techniques and much higher safety standards) and sometimes with different terminology. So it doesn't always translate

Anyone who really wants a detailed explanation of wood movement, I thoroughly recommend R, Bruce Hoadley's book "Understanding Wood: A Craftsman's Guide to Wood Technology" which is widely considered to be one of the most comprehensive books written on the subject and was a standard college texts when I was doing a qualification a number of years back - but it's hardly bedtime reading

BTW good luck with the gate
 
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If you look at the top edge of the timber, it's the growth rings which are the important bit, and if you want to go that way you'll need to orient your boards as above to get all the boards to cup outwards equally. But here's the rub - at college I was taught two alternative methods; in the first all the boards are set-up to cup outwards (or upwards), in the other method you alternate the boards so one cups outwards, the next inwards, the next outwards and so forth. Take your pick because in reality, it doesn't really matter how you do it.


BTW good luck with the gate

Many thanks for the explanation. So if you take the boards I've got which would be the outside side. Is the side that has the slightly larger V profile the outside with the growth rings facing toward the inside of the gate?
 
More than likely. Just don't depend on the guy who's been doing the machining to have been consistent
 
More than likely. Just don't depend on the guy who's been doing the machining to have been consistent
I'm I going to see huge cupping effect if it keep it that way - large V profile to the outside, or should I use the smaller V as the outside face as suggested by conny?
 
It is outdoors. And it's therefore likely to get wet. It's a gate, so it will get wet on both sides. So there may be cupping and rotting. That's why you should use treatred timber if at all possible (and seal the cut ends withj end seal - asl the yard) and also why you need to protect it with something once it's been installed. And yes, I think you worry a lot
 
It is outdoors. And it's therefore likely to get wet. It's a gate, so it will get wet on both sides. So there may be cupping and rotting. That's why you should use treatred timber if at all possible (and seal the cut ends withj end seal - asl the yard) and also why you need to protect it with something once it's been installed. And yes, I think you worry a lot
It is treated timber and will be sealed once hung but which side should I use in your opinion as the outside side of the gate - the fractionally larger V profile side with growth ring facing toward the inside of the gate or flip it around and use the smaller V profile and keep the growth rings facing toward the outside?
 
will be sealed once hung

as it's T&G used outdoors, I recommend using your stain or other finish before assembly. this will enable you to do the rebates and ends that will be inaccessible, and the entire tongue.

because it will shrink in dry weather, the bare strips of tongue will otherwise become visible and look unsightly. It is very difficult to stain them after assembly.
 

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