Tag Archives: carport

Steel to Plywood, Carport Over Tiny House, and Drip Edge at Fasia

This Wednesday the Pole Barn Guru answers reader questions about the possibility of adding steel roofing on top of existing plywood, some thoughts on a small metal carport over a tiny house, and the use of two-piece trims for fascia.

DEAR POLE BARN GURU: My garage has plywood on it already can I just put steel roofing right on to the roof or do I have to purlin it. ? No insulation in garage, rough wood with ridge cap. SUE in HINCKLEY

DEAR SUE: For best results, you will want to at least place 2×4 ‘purlins’ (stripping) on top of existing roof sheathing with 3-1/2″ face towards plywood. Screws into plywood or OSB only will have a limited resistance to uplift due to limited thickness of wood fibers to grip into. Make sure to use 30# felt or a synthetic underlayment on top of roof sheathing.


DEAR POLE BARN GURU: Hello, I just had a metal carport erected over my tiny house. The structure has 2″x2″ vertical supports every 45 inches. I would like to use high hat metal galvanized supports at the top of the skirting and behind the vertical board and baton style vinyl siding. My questions is if I notch the high hats so they recess passed the front of the vertical supports, so the top of the high hat is against the face of the vertical supports, will it destroy he integrity of the high hat that is needed for support to attach the vinyl siding to? The face of the high hat would have a screw through it and the tabs that exist from cutting the notch would be attached to the side of the vertical supports with a sheet metal screw also. R.J. in OSTEEN

DEAR R.J.: In my humble opinion, you are plowing lots of time, energy and hard-earned cash into something unlikely to be worth your investment. These light gauge steel carports are generally referred to as “blow aways”, because so many of them do (although here in snow country, they usually collapse from snow first). You will need to reach out to whoever provided engineering for your original build, as they will be best to advise you as to what can and cannot be done. Just make certain to get their design solution as an engineer sealed plan specific to your site, so when it fails, you are not personally hung out to dry.


DEAR POLE BARN GURU: From the research I have done, it seems most pole barn builders use an eave trim overlapping a fascia trim at the eave overhangs. Everlast doesn’t have an eave trim, so I ordered drip edge. I was planning to apply fascia trim and overlap the drip edge, but the overlap is only about 1/4″. Will this work? Perhaps you could show a detailed sketch of this area. Thank you. DAVID in WESTFIELD

DEAR DAVID: Building Codes do not require a drip edge with steel roofing and most builders do not use one. We tried overlapping eave trims with an L trim years ago and could never get a decent look out of it. Steel companies seemingly struggled to get correct angle to fit on top of a beveled fascia purlin, eave trims were press broken so were not 100% identical, list was endless. We went to just ordering L trims at dimension of face of fascia purlin plus 1/2″ for soffit and has worked out well. I wouldn’t try to use your proposed drip edge/fascia trim combination as proposed, as even if you were to get it to lay smoothly, drip edge will be in way of gutters.

Trying to Add a Carport on a Social Security Budget Reader

Trying to Add a Carport on a Social Security Budget

Reader BRIAN in WHITE CLOUD writes: “I am planning (hopefully as funds exists) a free standing 24 x 24 x 8 sidewall carport that will butt up to the front of our existing garage. I am planning to use 6×6 treated posts sunk to 48″ deep on a pad. I will also place (2) 1/2″ x 12″ long re-rod through the bottom of each post and add 2 or 3 bags of redi-mix around the bottom of each post. Spacing at 8′ on center with an engineered 24′ 4/12 truss notched into each post with a double 2×10 header notched into each post around the periphery of the building. 2×4 purlins on edge with steel roof. My question is 1. Does this sound structurally sound in Michigan or am I missing anything? 2) Should I add a post in center of truss span at each end? 3) Since we only live on SS I wish to try to keep costs down and wonder if I could downsize the posts to 4×4’s? Thanks!”

For sake of discussion I will assume “front” to be a gabled endwall. If so, and your existing garage is structurally sound, you can probably just add a ledger board securely attached, rather than needing another truss.

Provided this can be done, I would place four UC-4B treated posts at 12′ and 24′ from existing building (two on each sidewall) and entirely backfill holes with concrete (this is a roof only building, lack of concrete encasement will likely result in racking of building). No, these cannot be 4×4. Use a single truss on front endwall and a pair of trusses at 12′. 2x purlins, on edge, joist hung between trusses (or to ledger).

We could engineer and provide this building for you, utilizing site built trusses, to further reduce your investment, as well as it would be fully engineered. You won’t need to have headers (aka truss carriers) or a column at center of each endwall.

Adding a Post Frame Gable Extension

Adding a Post Frame Gable Extension

A roof line extension off a post frame gable endwall is an affordable method to cover porches, patios, or even as a carport. As opposed to attaching a single sloping (shed style) roof, it will not reduce headroom or block line-of-sight. It is also easier to build as it will not entail detailed flashings to prevent water infiltration at existing building wall.

Reader MATT in AUSTIN writes:

“In 2020 we had a pole barn built (36’G x 46’L). 5′ truss spacing and posts are set about every 12′ plus door sides, etc. On one gable end we knew we wanted a deck but figured we would handle it later ourselves. But now we are thinking about the deck cover being a gable extension. Looking at doing a 10′ gable extension over a 10′ deck. We can get an auger out to set posts, but getting trusses delivered and stood up might be tough. So can we just stick build the extension and tie it back to the building? I assume that would look like setting our new posts, building a copy of the end truss on our new end, then ridge and rafters? Given the deck will need a railing anyway, I am fine doing more posts than corner posts, including center post, though it would look better with 6×6 corners and 4×4 every 8-12′ (to support end truss and railing). I am totally open to hiring you to answer questions/do design if needed. I am sure we didn’t have an engineered design for our building (not site specific at least). We are built with BMC trusses that were project specific.”

Mike the Pole Barn Guru writes:

Thank you for your kind offer of hiring me however I am not a Texas Registered Professional Engineer or Architect, so I can only guide you in a general direction. Ultimately you should be able to take my recommendations to a Registered Professional who should be able to wrap this up with a nice, tidy bow.

Across your new deck end, you can place columns at corners and every 12 feet, tall enough to reach the roofline. A 4×4 will not be adequate to resist imposed loads, 6×6 may be (make sure whatever you do use is UC-4B treated for structural in ground use). Columns must be set on concrete footings at least six inches thick and provision must be made to prevent uplift.

As your existing structure has full length columns (to top of end truss), you can sandwich a rafter to face the existing truss, with tops of truss and rafter even. In all likelihood, this will be a 2×12 #2. Place a similar rafter on the outside face of new end columns, appropriately nailing (10d galvanized commons or even better Simpson SDS screws).

Dimensional lumber or plywood furring strips can be placed between high ribs of endwall steel, allowing for rafter to be attached without having to cut existing endwall panels. SDS screws will need to be appropriately longer to accomplish a sound structural attachment.

Between rafters, 2×6 #2 purlins can be placed on edge, using LU26 Simpson hangers (or equal).

Post Frame Propane Transfer Stations

Post Frame Propane Transfer Stations

Earlier this year the propane tank on our barbeque grill decided to run empty. The solution – load up the tank and haul it to the propane transfer station at nearby Sisseton for a refill.

Propane is a hydrocarbon (C3H8) and is sometimes referred to as liquefied petroleum gas, LP-gas, or LPG. Propane is produced from both natural gas processing and crude oil refining, in roughly equal amounts from each source. Nearly 97 percent of propane consumed in the United States is produced in North America. It is nontoxic, colorless, and virtually odorless. As with natural gas, an identifying odor is added so the gas can be readily detected.

Storing propane tanks outdoors or in an open shed provides the most security. Storing propane tanks indoors can be dangerous. Each tank contains pressured gas, which can explode. So storing propane tanks in your home is simply not safe. Additionally, the tanks should not be stored in enclosed areas such as garages and basements. The tanks can explode at temperatures above 120 F.

Now I was fairly amazed when the propane dealer refilled my tank – inside an enclosed building! I took a few steps back and made sure my Chevrolet Avalanche would block the path of any shrapnel when the shed exploded.

Luckily for the man doing the filling and my vehicle, the propane filling building did not go off!
Whether you are operating a commercial propane transfer station or merely the backyard meat burning warrior, safety coverings can be quite affordable.

Whether carport or shed, the investment per square foot covered will be roughly similar.
For commercial propane transfer stations, covering one or both post frame building ends allows for significant airflow while holding costs down. Roof only post frame buildings can become costly, especially as the gain height, as they have no walls to aid in transferring wind shear loads from the roof to the ground.