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Discussion Starter #1
Hello forumites,

I'm working on building a ground level deck with patio style single pitch roof over my pizza oven.

I do not know whether my thinking is correct, whether the dimensions of timber are appropriate. Any advice I would certainly appreciate before pulling the trigger on this.

Badly drawn sketch here:



Photo of area I been working on here:



Concept idea lifted off the internet:



Basically given my budget I would like to use 4by4 for posts (6 posts), and long 4by4s for beams front and back across the width of the patio (nodged on top of the corner posts). Then 2by6s for horizontal beams front to back on the sides for stability. I would then place 2by4s vertically as roof rafters and a light tin roof on top. Does that do it, or will it blow or blow?


Thanks a lot.

Simon
 

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that is a very nice looking structure :)

i think your 4x4's will be fine as long as everything is bolted together properly.
now, keep in mind, 4x4's are much less dimensionally stable than 6x6 and can twist and bow. when picks boards, look for dry ones that are straight.
 

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Discussion Starter #5
that is a very nice looking structure :)

i think your 4x4's will be fine as long as everything is bolted together properly.
now, keep in mind, 4x4's are much less dimensionally stable than 6x6 and can twist and bow. when picks boards, look for dry ones that are straight.
Thanks for your comments Fix'n it. I'm in Japan. Here the thickest posts I've seen in the lumber yard are 10,5cmx10,5cm...it is also possible to special order 12cm by 12cm, which would be just shy of 5by5 actual measurement. So 6x6 would be hard to come by, but given your advice I am now considering at least 10.5x10.5s ...

Then the added trouble (or challenge) is that the max post and beam length here is 4m, where I will need 4,5m to get all across the oven and deck area front and back. I guess a good carpenter would just join two beams with a scarf joint but i've never wrestled with that, so there's that also.
 

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Thanks for your comments Fix'n it. I'm in Japan. Here the thickest posts I've seen in the lumber yard are 10,5cmx10,5cm...it is also possible to special order 12cm by 12cm, which would be just shy of 5by5 actual measurement. So 6x6 would be hard to come by, but given your advice I am now considering at least 10.5x10.5s ...

Then the added trouble (or challenge) is that the max post and beam length here is 4m, where I will need 4,5m to get all across the oven and deck area front and back. I guess a good carpenter would just join two beams with a scarf joint but i've never wrestled with that, so there's that also.
what you could (perhaps ?) do. go with the 10.5cm posts and then wrap them with 1x boards. but this would mostly be for aesthetics . if your good with the 10.5, just go with them.

btw, i would LOVE to visit Japan !!!
 

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Discussion Starter #9
I would want something that is rectangle shape for a beam like a 4 x 6"
The beams can be a but join over the center posts
Interesting, I guess the rectangular shape would be for aesthetic reasons? I will look around a bit more and see regarding post and beam sizes and availability over here. Thing is, Japan has this big carpentry tradition, so I guess I could order anything to size from the lumber yard, but man it's not cheap!

On the joint, I also haven't decided. More research is needed. I did read somewhere that a beam joint should not be placed right over a post due to the crowning of the joining beams which would naturally tend to occur right over a post, so a joint there would be a weak point - instead a joint should be placed offset on either side of the post where there would be a knee brace. In that case it would have to be some kind of interlocking scarf joint, or something supported by steel braces.
 

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Interesting, I guess the rectangular shape would be for aesthetic reasons? I will look around a bit more and see regarding post and beam sizes and availability over here. Thing is, Japan has this big carpentry tradition, so I guess I could order anything to size from the lumber yard, but man it's not cheap!

On the joint, I also haven't decided. More research is needed. I did read somewhere that a beam joint should not be placed right over a post due to the crowning of the joining beams which would naturally tend to occur right over a post, so a joint there would be a weak point - instead a joint should be placed offset on either side of the post where there would be a knee brace. In that case it would have to be some kind of interlocking scarf joint, or something supported by steel braces.
A rectangle will have an obvious crown so you know which is up and is less likely to sag. The only time square is used it is tall enough and the rest is for looks like in timber framing everything is over kill.



Old school was to build a beam out of 2ply or 3 ply and the followed what you have been reading.

That has long gone over here, If we have 6 posts 10 ft apart we get 5 beams 10 ft long. And it is the same if we are building the beam out of 2x?

A 4x6 for a beam here would be cheating, our min would be a 2 ply 2x10.

We don't use 4x4 for anything but fence posts now.
 

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Beginner. i have an awesome idea for you. are you opposed to a little extra (not hard)work ? and maybe have to borrow a few extra tools ?
 

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Discussion Starter #12
A rectangle will have an obvious crown so you know which is up and is less likely to sag. The only time square is used it is tall enough and the rest is for looks like in timber framing everything is over kill.



Old school was to build a beam out of 2ply or 3 ply and the followed what you have been reading.

That has long gone over here, If we have 6 posts 10 ft apart we get 5 beams 10 ft long. And it is the same if we are building the beam out of 2x?

A 4x6 for a beam here would be cheating, our min would be a 2 ply 2x10.

We don't use 4x4 for anything but fence posts now.
Thanks for the info and perspectives of building in the US. I do realise that everything generally is 'bigger' in the states - definitely compared to Japan where things generally are 'smaller' than everywhere else. So I guess I will strike a balance also to fit this into the surroundings. Originally I would have preferred to pour concrete for the floor, but as you see I've been already struggling with cutting into the hillside, making retaining wall, and leveling, so I am pretty fed up with the last months' of concrete work -therefore now thinking of making a 2by4 wooden deck floor, but concrete would probably require less maintenance.....well I am straying off topic here.

On using 2by? for beams I have also considered that and may do it, as it might look better and for example a 2by8 beam might even be stronger than a 4by4 beam given I learned that the 4by4 is probably milled from soft heart wood. But the reason I am not sure is due to the joining of the 2by beam on the posts: It can be done I guess by cutting into the post to let the 2by beam rest in side the cut rather than just bolting to the side...but such cut would invite more water/rot than bolting a thicker beam on top of the supporting posts and then not exposing any end cut to the weather as much.
 

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Thanks for the info and perspectives of building in the US. I do realise that everything generally is 'bigger' in the states - definitely compared to Japan where things generally are 'smaller' than everywhere else. So I guess I will strike a balance also to fit this into the surroundings. Originally I would have preferred to pour concrete for the floor, but as you see I've been already struggling with cutting into the hillside, making retaining wall, and leveling, so I am pretty fed up with the last months' of concrete work -therefore now thinking of making a 2by4 wooden deck floor, but concrete would probably require less maintenance.....well I am straying off topic here.

On using 2by? for beams I have also considered that and may do it, as it might look better and for example a 2by8 beam might even be stronger than a 4by4 beam given I learned that the 4by4 is probably milled from soft heart wood. But the reason I am not sure is due to the joining of the 2by beam on the posts: It can be done I guess by cutting into the post to let the 2by beam rest in side the cut rather than just bolting to the side...but such cut would invite more water/rot than bolting a thicker beam on top of the supporting posts and then not exposing any end cut to the weather as much.
That would be a 2 ply 2x?

This is what you would see here for beams joining over a post. Never bolted to the side of a post.



 

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I'm all ears.
ok. it wouldn't be all that hard to make a "glue laminated beam".
this way you could use what lumber you can get, and make the beam/s you need.

now, it could be possible that you could just order what you need for not much more and make things easier on yourself. i'm just giving options.

btw, if you don't mind me asking = are you Japanese ? ever been to the states ? from the states and moved there ?
 

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Your 4x4 beams on the 2.4m span may only be adequate for about 20 pounds per square foot for the roof framing and roofing materials or about 300 lbs point load, but not both. So, if the roof system weighs 10 psf, and the person putting the roof on weighs 150 lbs, it might be strong enough, but then again it might not be. Unless your roofing system is fairly light, or you can manage to put it on without anyone climbing on top of it (I did a shed recently almost that large, where we framed and finished the roof and put it up as a finished unit, but it took 6 guys to put it up), I suggest using 4x6 beams or double up 2x6s.
 

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Discussion Starter #17
That would be a 2 ply 2x?

This is what you would see here for beams joining over a post. Never bolted to the side of a post.



Thanks Nealtw. I am infatuated with wood joinery. In a perfect world I would have time, tools and means to work on pure wood joinery, it is beautiful and long lasting and a scarf joint with wood pegs would look awesome, but alas...

...in real life adn given time, money and skill constraints, the option you share is definitely viable. I guess I am seeing 2bys sistered, and then the middle plate continues across the post to provide the stability, where the two on the outside buttjoin over the post - that's my take from the image? I will look around and see what kind of post brackets are commonly available for such option over here and consider this some more. But this is good. Thanks again.
 

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Thanks Nealtw. I am infatuated with wood joinery. In a perfect world I would have time, tools and means to work on pure wood joinery, it is beautiful and long lasting and a scarf joint with wood pegs would look awesome, but alas...

...in real life adn given time, money and skill constraints, the option you share is definitely viable. I guess I am seeing 2bys sistered, and then the middle plate continues across the post to provide the stability, where the two on the outside buttjoin over the post - that's my take from the image? I will look around and see what kind of post brackets are commonly available for such option over here and consider this some more. But this is good. Thanks again.
If 2 are called for the middle one can join anywhere but if three are required they all join in the beam.
 

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Discussion Starter #19
Your 4x4 beams on the 2.4m span may only be adequate for about 20 pounds per square foot for the roof framing and roofing materials or about 300 lbs point load, but not both. So, if the roof system weighs 10 psf, and the person putting the roof on weighs 150 lbs, it might be strong enough, but then again it might not be. Unless your roofing system is fairly light, or you can manage to put it on without anyone climbing on top of it (I did a shed recently almost that large, where we framed and finished the roof and put it up as a finished unit, but it took 6 guys to put it up), I suggest using 4x6 beams or double up 2x6s.
Thanks Hotrodx10, that's a good point of caution. My intended roof would indeed be very light, so I think the deadload (?) would be okay, but I am heavier than 150 lbs so yes that is a point of concern. I maybe could go with sistered 2by4s, or even 2by6s. I will think about it...

The final external height of the roof system is a limitation for me, for 2 reasons: one being that the structure is fairly short given the limitations of the sloping hill and so it would look weird with a very high but short roof wouldn't it...and the other being the limited length of the chimney I have for the pizza oven. It must penetrate the roof by a certain margin. Otherwise I have to splurge out for an additional 3-4 ft of chimney to extension. Double walled insulated chimney isn't cheap to buy from the US and send over here...So, thinking about this, any decision will affect weight, height...and budget! But thank you for the inputs.
 

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ok. it wouldn't be all that hard to make a "glue laminated beam".
this way you could use what lumber you can get, and make the beam/s you need.

now, it could be possible that you could just order what you need for not much more and make things easier on yourself. i'm just giving options.

btw, if you don't mind me asking = are you Japanese ? ever been to the states ? from the states and moved there ?
Thanks for the tip, that's a good option, to glue for instance two 2by6 or 2by8 to get to a desired size/thickness. I'm still debating and it's raining a lot here these days so actually pulling the trigger on all the wood may take a few weeks.

I am not Japanese, no, could never pass as that. But been here almost 10 years now. I am originally from Europe, and have often been toying with the thought to go back home. I've got a wife and daughter so it would be a bit of a move, these days especially with covid and all. So we are here temporarily for a long time now. There is a french saying goes something like 'the temporary becomes the permanent', often happens that way doesnt it... How about yourself, from the US?
 
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