Construction question?

[Boomyal]

What would be the longest span you would want to make using 4 x 4's as the header support for a lightly loaded roof? This would be for a shed roof that will use 2 x 6's, 16" on center tied to the adjoining building and run out over a header of a free standing wall.<br /><br />The outer wall will be built using the appropriate number of 4 x 4 posts set on top of concrete pedestals with a header across the top of them. The roofing material will be corrugated aluminum or steel so there will not be a lot of weight on the outer wall.

 

[steamboatwilly]

Re: Construction question?

I helped my Sister-in-law built a shed same size as yours.I put the header ten(possibly twelve)feet.I used four by six.I turned them wrong.I put four inches vertical and six inches horizontal.They are sagging an inch or two.I dont think I would go over eight feet.Maybe somebody else will say something.

 

[one more cast]

Re: Construction question?

I built a porch back in the 80's and spaced them 6' and it holds 3 feet of snow without sag so with a light load I would say maybe 10'. Personally I also wouldn't go over 8'.<br /><br /> My porch was/is 8'x 12'

 

[Mark42]

Re: Construction question?

Why use 4x4 as the header? I suggest you use two 2x8 bolted to the 4x4 posts. That is easily good for a 8' span. If you are going to use the 4x4, keep the span to 4'.

 

[LubeDude]

Re: Construction question?

Mark is right on Boomer, 4' for a 4X4. Basic door or window header. 6' for 2 2X6s. 8' for 2 2X8s, and 10' for 2 2X10s. I always over build, so I always go to the next size but for a shed, you will be fine with what I posted.

 

[txswinner]

Re: Construction question?

4' is best with 8 foot 4X4 if 10' you can go 5' annd max 12 4X4 6' Note each end and middle support. Check cost and go for it.

 

[Boomyal]

Re: Construction question?

Ok all, if I'm going with a 6' span, I should go with doubled up 2x6's. One nice thing about that is that I can overlap the joints so that I don't have to hit the support posts dead on with the butted joints.<br /><br />Sound good?

 

[EZLoader]

Re: Construction question?

The rule of thumb for headers is an inch of depth per foot of run. <br /><br />Doubled 2x6s sounds good for 6' span! Have you considered spanning the standard 8'instead of 6' to avoid cutting 2' off your header stock? It will also save you an upright post over 24'. I would use 8' 4"x8" header stock set on top of my upright posts with metal hangers for a strong and clean looking frame. Here is an example I found on the web that is similar to what I'm talking about.<br /><br />

<br /><br />Since we don't get that much heavy snow around here just go out and rake it off before the load becomes too heavy for the few times we do.

 

[Boomyal]

Re: Construction question?

Originally posted by EZLoader:<br /> It will also save you an upright post over 24'.

Can't grasp what you mean here EZ! Gotchya on the rest of it. I'm going to be helping a friend on this project. He's over on 96th just east of 152nd Ave. The roof will have a decent slope on it.<br /><br />Do you think I should set the roof joists on top of the wall plate (as pictured) or hang them off the face of it using the appropriate hangers?

 

[tashasdaddy]

Re: Construction question?

boomyal, i'm retired contractor. if your total header is 24' long i would use a double 2x6 header sandwich 1/2" plywood blocks 3"x5 1/2" every 16 inches (this way header is same width as 4x4) one side of the header should me made from these lengths 4' 16' 4'. the other side use 2 12' 2x6 3 12# galvinized nails every 16". this will give you one continous header, will help keep everything straight and level. should last for the next 100 years. if you use PT

 

[EZLoader]

Re: Construction question?

Boomyal, you said you were spacing your posts 6' on center and I just assumed the carport must be 24'deep (5 upright posts; 6' o.c.). If you set the posts at 8' on center you save 1 upright post over 24'. I thought this was for your 20' boat.<br /><br />Set the outside header beam on top of the 4x4 upright posts. Set the roof rafters on top of the outside header and let them cantilever out over the header beam so that you get some extra rain protection. <br /><br />Metal hangers on the wall ledger would work fine too.<br /><br />Tashasdaddy is right...you can build your header beam nailing together 2xs with 1/2" plywood spacers as he described above. The choice between doing that and buying solid 4x's is usually based on cost and availability. If you build them up the way he described your could also notch your 4x4 upright posts leaving a 1/2" tenon to accept the built up 2x header beams. <br /><br />Which way you finally decide to go will depend on your existing wall, you post heights, your desired roof slope and carport opening height, etc..<br /><br />152nd Ave is on my regular daily commute...I go by their every day. Your friend must be just north of York Elementary. I'd be glad to stop by and take a look at your project for you.

 

[Boomyal]

Re: Construction question?

Here is the deal. The shed will be 30' long. I like the idea of making up the outer header with 2x6's and 1/2" spacers. What lengths would be good to make up both sides of the 30' header. And if the spacers are only 5" each, should I use a longer spacer at each butt joint?<br /><br />tashasdaddy, I don't understand this statement.<br />"sandwich 1/2" plywood blocks 3"x5 1/2" every 16 inches"<br />Are you saying 3.5" x 5" blocks of 1/2" ply?<br /><br />I figured to use T straps to secure the 4x4 uprights to the header. Should I use them on both sides? I will use a 4x4 post every 6'. Also what is the best way to secure the joists over the top of the header?<br /><br />Back to the wall plate. This shed will be anchored to a conventional plywood sheeted wall with 2x4's behind it every 16". I will lag the plate to the wall, but my question is whether to place the roof joists over the top of the plate or just hang them off the face of the plate with the appropriate hangers.<br /><br />Initialy we will not sheet the outer wall. Should I use some large plywood upper corner gussets to secure the outer wall from racking.<br /><br />EZ, I saw how they did it in your picture but I don't want to go to that extent.<br /><br />Tomorrow morning I will go over to make a material list.

 

[EZLoader]

Re: Construction question?

With 6' o.c. spacing and 30' length you could attempt to find 2 straight 16's and cut them to 2-15's for one side and use 8/14/8 for the second side. Your joints just won't rest on any posts. Nail them with galvanized 12#s as Tashasdaddy said above. <br /><br />The 3" wide x 5 1/2" tall plywood spacers placed between the doubled 2x6s are meant to increase the width of your "made up beam" width to a full 3 1/2" (2 x 1.5" = 3" + 1/2" spacer = 3.5"). This makes your beam the same 3.5" width as the upright 4x4 posts. Longer spacers at the butt joints can't hurt since you will be placing more nails at that point. <br /><br />Re: Beam to post connection - T-straps on both sides of the posts would work ok but even better would be the 4x4 metal post caps already specially made for that purpose.<br />

<br /> http://www.strongtie.com/products/highwind/PostColumnCaps.html <br /><br /> http://www.strongtie.com/products/highwind/PostColumnBases.html <br /><br />You can toe nail the rafters to the top of the beam or better yet use metal hurricane/seismic hold down ties like this:<br /> http://www.strongtie.com/products/highwind/TrussRafter-WDTP.html <br /><br />Lagging the ledger board to the wall studs is typical and you can either place the rafters on top of the ledger board or secure them to it using individual metal rafter hangers. Either way works fine. You may decide which one based on your desired rafter/joist height and pitch and the side wall layout conditions. If you place them above the ledger, add blocking between rafters to prevent twisting.<br /><br />metal rafter hanger:<br />

<br /> http://www.strongtie.com/products/connectors/RR.html#gallery <br /><br />Add plywood gussets and/or 45 degree angled brackets to the posts and beam (like in the above photo) to stiffen the frame and minimize shear.<br /><br />If you go to Lumbermans, Parr, Milwaukee Lumber with your plan they will do a material takeoff and pricing for you and answer questions/make suggestions. I'm not sure if Home Depot/Lowes will do that.

 

[tashasdaddy]

Re: Construction question?

boomyal, send me your email i'll send you detailed drawing of how i would build it. please give me the width and length measurements. bob tashasdaddy@comcast.net