I think I know what the answer will be, but I wanted to see what opinions you guys may have….I have an existing 4″ slab, used for basketball court that I want to use for a shop floor….Kids gone now and slab not being used for anything….Anyway, next to the slab is a clearstory shop 20 x 24 that I built 20 some years ago on poles in the ground that is 14″ higher than basketball court slab…..I would like to build a clearstory to match on the existing slab….The slab is 30 x 40……I was thinking of cutting out the slab at the corners and middle of edges, digging 12″ dia holes down below frost line, using 6 x 6 posts/concrete, headers, framing clearstory roof and filling in walls under the roof…..I am open for suggestions….Alex
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Replies
May be easier to drill holes and epoxy bolts in so you can use some post-setting hardware. Others here can tell you better what to do, but breaking out the concrete sounds like too much work for me!
Possible to dig just outside the slab perimeter?
Be way easier.
Pour a ribbon of crete around the inside perimeter after the building is up?
I agree. But, cutting a chunk out of the concrete really only adds a trip to the rental and half a day so either way, I think he's got himself a fun project. Bob's next test date: 12/10/07
Quote of the day: "...can't be done, it will take too long, not enough pipeline capacity, yada yada but yet they don't apply the same skepticism to their own "solutions" such as wind and biofuels"
Alex,
If I understand you goal you want to enclose the slab as cheaply as possible?
I don't know where you are but if you are anywhere near small and modest sized saw mills you could do well by shopping there instead of a lumberyard..
What I would do is put a bottom plate of decay resitant wood like white oak. (.80 cents/ bd.ft.) Rotary drill lag bolts into the slab to hold the bottom plate down. Then do a post and beam of railroad ties (before they are treated of course). currantly railroad ties cost about $20.00 each and are 9x6" by 81/2 feet long.. You could set them at 8 foot intervals and connect them at the top with a top plate of the same thing..
Trusses across to tie the sides and then hand frame roof trusses from sawmill wood.
Cover the roof and sides with sawn planks Depending on the size of building you make your costs would be nominal compared to lumberyard prices..
Thanks for your replys......It sounds like maybe digging out from under the slab at the corners and middle of the edge, pouring concrete footings, bolting post on top of slab, then running headers and roof framing, tin roof and fill in walls.......Ok, got to get to digging......thanks again, Alex
I think what Frenchy was saying was that if you bolt down a plate and use rr ties, there is no need for breaking holes in slab. I would avoid that, if at all possible, but I'm a lazy potlicker.
I'd leave the slab alone.
I'd drill/dig holes to below frost, dump in a dry bag or two of concrete premix, run a rim of 2x treated around the slab, set the posts right against the 2x, and so forth. My shop is not much different except the slab goes to the outside of the posts and the treated 2x is on the outside. If you put treated 2x on both the inside and outside of your posts with the tops of said 2x level with each other, you could lay a flat treated 2x on top of them as a sort of bottom plate (to keep critters from invading the wall from the bottom).
I'd suggest that you shop around because you can still get 6x6 CCA treated posts (and bigger).
Another possibility is using screwed together 2x6 treated as the posts themselves. There's a company, Cleary Buildings, that puts up ag buildings and garages all over around here. All are built with posts that are put together onsite made of three ACQ 2x6 screwed together. They claim the three 2x6s will last longer than a 6x6 because there is more treatment in the post.
And, on the other hand, cut and breaking out a bit of concrete isn't the end of the world.
Have fun!
Ok, now we are getting somewhere......Seems like I need to either shovel/pick or find some kind of equipment to dig under the slab in four corners and middle of the edge to support the post/poles....I need to bolt down a 2 x 6 pt sill, then frame on top of that.....I just needed good support for the roof in the corners and half way in between to run headers leaving it mostly open on the ends.....I am in Tennessee and am blessed with good ole hard clay, so equipment is preferred for the digging....Small backhoe, jack hammer with spade attachment, young/strong back/hardworking guy.....any suggestions?????????
Not sure if I made myself clear. I'm thinking direct bury 6x6 CCA right next to the existing slab, not actually pouring under the slab.I used a skid-steer mounted phd to drill the holes.Attached is a pic of my slab prep.
Ohhhhhhhhhhhh.....I see....I was going to cut out the corners and middle of edge of the slab, dig holes, put post in holes with concrete to have the post built into the walls......hmmmmmm, so you have exposed posts with the walls inside them......I'd like to see how you framed your walls and roof system......If you have pics, please post.......
I've done it two ways.My shop has horizontal 2x on the outside of the posts, 1 1/2" foam cut to fit, sheetrock screwed to same horizontals. I know that not much of an effective r value, but I only keep it from freezing and it's rarely very cold here.I've also placed the horizontals in between the posts and flat (horizontal) instead of the vertical way like my shop is. Finish out like any post wall section.
I like it......I may cheat a little and make more space for insulation, but keep the post and beam look intact......Thanks for your time.....Alex
Thats the method I was going for.
They can't get your Goat if you don't tell them where it is hidden.