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Question about the spacing on porch railings. This is a concrete porch pad, not a wooden deck.
The particulars:
Porch is 20' end to end (plus 4" on both sides to keep posts away from the edge)
I'm thinking of putting one post on each end, and one in the middle, so, roughly, 10' railing
Everything will be pressure-treated lumber
There will be a top and bottom rail, with turned vertical balusters place 4" on center
Here are the questions:
Is this good enough, or do I need the posts closer together (shorter runs between posts)?
Alternatively, I was thinking of a simple 4x4 at about 5' just between the porch and the bottom rail to prevent sagging. Would this work instead of a full post if the 10' spacing is too far apart?
Mike
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4x4 post in the center of the 10' rails sound good.
Balusters on 4" cc sounds good.
I think your plan is well thought out.
Steve
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WaterlooMark 02/9/2020
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I believe a 10ft PT rail will sag unless it's blocked up in the center.
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I agree with Neil. I would put a “post” in between the three you plan, but would have it go only to the lower cross piece. This gives you the look of 10 feet but the support you need
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What are the dimensions of your top and bottom rails?
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When I was designing my 16' x 36' deck, I started with 2 corner posts and a center post on the 16' ends. After some thinking, I decided to put 2 equally spaced posts on the 16' ends, making 3 equal spaces instead of 3. This worked out really well, design and construction wise. I was worried about sagging and with the shorter span, no worries.
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Garry
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(04-04-2020, 06:49 PM)goaliedad Wrote: I agree with Neil. I would put a “post” in between the three you plan, but would have it go only to the lower cross piece. This gives you the look of 10 feet but the support you need
What he said. I have some vinyl railing around my slab deck, and it came with two little stub posts that go from the slab to the bottom of the bottom rail. Keeps it from sagging, but doesn't visually take away from the span.
I would also keep the space between the pickets to a max of what the building codes allow (4 inch?) with stair baluster spacing, just because.
Tom
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(04-04-2020, 02:42 PM)Snipe Hunter Wrote: I believe a 10ft PT rail will sag unless it's blocked up in the center.
I do too. Thus the......4x4 post in the center.
Steve
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WaterlooMark 02/9/2020
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I have a general rule (I made up). No single no load 2x4 on edge will span more than 7 feet. Laying flat- 3 feet.
It depends on how much load, but I choose lumber with a slight even crown and put the crown up.
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4" spacing on balusters is good. The max limit in my area is 4.5", it has to do with kids potentially getting heads stuck. I have always done a maximum of 4" measured to the narrowest point on the baluster, if you are using turned balusters.
