I’m planning on starting a deck in a few months. I’ve built several over the years, but I’ve never had to fasten the legder board to concrete block. Does anyone know of any good fasteners or methods for attaching the ledger. Also should I use washers in between the back of the board and the block for spacers to allow water to drain behind it or should I just bend flashing and tuck it under the vinyl siding?
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Is that your only option , to attach it to block..... you might want to try drilling a hole through both sides of the block. If possible run long bolts staggered from the inside of the block wall and out thru your header joist that will be carrying the other joists. Pressure treated spacers 1/2`` thick placed close to the bolts should do the job. Pro Trim has a new hand bendable vinyl out now that you can place over the header and under your hangers you might want to take a look at that.
http://www.pro-trim.com
There was a thread on this about a year ago which pointed out how movement in the deck could pull on the block, thus loosening them. I can't elaborate but in it there was mention of attaching through the block and directly to the joists. Someone else around here could fill in the details, but if it were me I'd be reluctant to attach directly to block or brick. -----------------------------------------------------------
FT Job Wanted: Chicago, north side/North Shore burbs. http://forums.taunton.com/n/mb/message.asp?webtag=tp-breaktime&msg=70809.1
I'm in a similar situation to t12hoops, except that the wall I'll have to attach the ledger to is brick, and I'm reluctant to drill through the wall (suggested in the Taunton book) because the electrical box is on the other side.
Have you considered just building it freestanding? Putting posts in might be easier and you won't have the worry of moisture penetration.
How do you recommend building it free standing. Should I just stay off the block/house/siding an inch. The deck will only be sitting up about a foot off the ground near the house. I was hopping to directly fasten to the block so I wouldn't have to dig and pour twice as many footings. I would probably have to use a girder on both ends of the deck to support it. I'm trying to cut my labor and material costs so I figured attaching a ledger directly to the block would be the fastest. Also if I stay off the house how would I get behind the band board to face nail the joists. Any suggestions would be great. Thanks.
The reason i asked if it attaching to block was your only option was, in some case`s the deck can be attached above the block wall and to the frame depending how the structure was built. Free standing the deck on beams is another option, but it would have to be double cross braced underneath to stop it from racking.Even then i would still want to have some sort of fasting system to stop the deck from pulling away from the building.Maybe you could also take steel banding slide it in under the sill about 2 ft in and nail it to the bottom side of the floor joist, then take the other end and fasten it to the floor joist of the deck as tightly as possible. Just some food for thought ok!
Even then i would still want to have some sort of fasting system to stop the deck from pulling away from the building.
If adequately braced and constructed, I don't see the need for attaching it to the structure. If there is so much concern that the deck is going to move, then someone needs to rethink the methods involved in construction. Why build it freestanding if you're going to tie it to the house anyway? And the detail of fastening it to the house would need to be almost as stout as a ledger, as now you are coping not with shear, but lateral forces that would require significant number of bolts/nails/screws. And the best of these would be thru-bolts, and if you're gonna tie the deck to the house with thru bolts, you might as well use a ledger. Tying a deck to a house with a few Simpson clips and 10d nails just won't hack it if the mass of deck decides to take a lateral journey away from the house.
My .02, fwiw.
"I am the master of my fate, I am the captain of my soul." Invictus, by Henley.
I did mention as one option to run bolts thru the block and the header and i agree with the statement about fastening wood on the inside of the block wall thats even better.The other way was creating 2 beams and i mentioned double crossbracing them (meaning in two different directions)to prevent racking.The straps like i said was just food for thought but that deck does need to remain stationary and safe above all else when all is said and done.
My buddy has a similar problem, only worse. He plans to add the deck to a wood frame wall finished with EFIS. The existing house has finished sheetrock walls and ceilings and carpeted floors - no access to the the back of the rim joist. Any suggestions?
Old scout,
All i can tell you on that is fastening your header of the deck to the frame of the building is the best option to go with, beyond that option i`m guessing that you have already read in my above post.
I probably could build it free standing. The placement of the sliding door does not allow me to fasten the ledger above the block foundation. I also don't think I could access the back of the block to run thru bolts into a 2x4 backer. If I do build it free standing how far do you suggest i stay away from the block/house/siding. I will also have to pour twice as many footings to support both ends of the deck. Not real sure how to go about. Let me know what you think. Thanks
You might want to take a look at this publication. http://www.fairfaxcounty.gov/dpwes/publications/decks/I know it has information on freestanding decks.ForrestCraftwork Construction LLC
Thanks!
What a great resource! Thank you.
I've held up replacing my torn-down-last-yeardeck because I'm unhappy with the fastening structure. Short of rebuilding my kitchen.....
I am going to replace it with a free-standing structure, and this is one of the best thought out planning systems I have seen.Quality repairs for your home.
AaronR ConstructionVancouver, Canada
I don`t know how big of a deck your planning on, but if you keep the size down you should be able to get by with 4 footings and two beams. Keep the deck close to the wall .
Here in NC, code requires that through bolting to block wall be "backed up" with treated 2x on the other side of the wall. Preferable to run the backing as one long piece. This seems to really consolidate the ledger. Never a callback.
Also, is there finished space on the other side of the block wall? I can't imagine why else to flash a block wall. And if so, then through bolting seems like a last resort.