How to Safely Attach a Deck to a House | This Old House

This Old House general contractor Tom Silva shows how to save a wood deck from a catastrophic collapse.

Tom helped a homeowner repair a deck that was in imminent danger of collapsing due to poor building practices. Underneath, Tom found that a couple of nails were the only things holding the deck's ledger board to the house. Using framing lumber and a sledgehammer, Tom pushed the deck back toward the house and back up to the proper height. With the deck in the proper position, Tom fastened the ledger board to the rim joist of the house with lag screws. For additional support, and to prevent the ledger board from splitting, Tom also used masonry bolts to fasten the ledger board to the stone foundation. He also found that the original deck builder used joist hangers that were too small for the 2x10 joists, so he installed larger-sized timber hangers (designed for engineered lumber) for additional support.

Tools for How to Safely Attach a Deck to a House:
- Sledgehammer
- Circular saw
- Drill/driver
- Impact wrench
- Hammer drill with 1/2-inch-diameter masonry bit

Shopping list for How to Safely Attach a Deck to a House:
- 2x4s and 2x6s_-inch x 10-inch galvanized lag screws with washers
- _-inch x 10-inch masonry wedge anchors
- Pressure-treated 2x4
- Engineered-lumber joist hangers

Joist hangers, masonry bolts and lag screws can be found at your local home center or lumberyard.

About This Old House TV:
This Old House is America's first and most trusted home improvement show. Each season, we renovate two different historic homes—one step at a time—featuring quality craftsmanship and the latest in modern technology. We demystify home improvement and provide ideas and information, so that whether you are doing it yourself or hiring out contractors, you'll know the right way to do things and the right questions to ask. Our experts Norm Abram, Tom Silva, Richard Trethewey, Roger Cook and host Kevin O'Connor give you the tools you need to protect and preserve your greatest investment—your home.

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How to Safely Attach a Deck to a House | This Old House

[Jbritehi]

Enlarging and going over the timber hanger was a great move. They're a real pain to take off.
Great vid!

[joesmith-vknx]

Nothing better then watching a PRO. Thanks Mr. SILVA

[lcaunan]

Mr. Silva gives very detailed instruction.

He made me smile when he started jumping on the deck. He reminded me of a small child 😂

[pasquarielloanthony]

wow. look at those antique tools! We've come so far in so few years. and the cellphone on his hip too.

[keithamundson]

Tom I always watch this old house when I can. You guys are great 👍.

[phrenic]

Thank you so much for this video. I've been trying to find info on installing my new ledger with the top half fastened to the rim joist and the bottom half into my cinder block foundation wall. This is exactly what I was invisioninig and made me feel a lot better about it.

[rubbersole]

Uttered by every man doing a repair or lashing something ain't going anywhere."

[michaelb]

I've watched this video like 7 times idk why it's interesting every time.

[Roadtrip]

What about flashing for the ledger board and some caulking to prevent water from getting down between the ledger board and sill/foundation????

[stevekluesner]

I still tend to like setting some posts running a beam or some carriage boards and y bracing rather than attaching that to the house . But this looks good if your going that way. AND I really liked the way that he got it back up into proper position. I am still in question as to whether the area between that "ledger" and the house is well protected from water (and insect ?) damage ?? Properly flashed, etc ???

[princedax]

I always enjoy these short videos especially when I see they are using the same exact power tools that I have it's like hay I got the right tools for the job

[neomatrix]

Another great video and I've learned again more thanks for sharing

[Michaelkx]

when useing those type of masonry bolt back the nut off to the end of it to make sure you dont mess up the threads when you are hitting it with the hammer its not something that will happen all the time but i have seen it before

[spadina]

4:30 buddy blew out the concrete hammering and spun out the anchor lmao. Tommy didn't have the heart to tell him

[Lawomenshoops]

It’s best to use screws into the timber hangers. Also for the temporary supports, they should use screws. Much easier to take out than nails.

[Yangar]

Always bring the nut to the tip of the bolt when hammering, the threads will be saved from getting damaged.

[spookerr]

I used 4x4 pressure treated posts (6) on my 9'x12' composite deck and legged up my deck which is already lagged to house.

[tomrunning]

I just had my inspection on my new deck and they want a few hangers that connect the deck truss to the house truss through the ledger board. They are saying the joist hangers are only connected to the ledger board and could pull off the house. Do they make some special hangers to do this? This is a 10'x18' deck with 2x10 trusses at 12 centers because of the composite deck boards and is only 7 feet off the ground. Also the ledger board is bolted with two 1/2" carriage bolts in every joist space.

[gregmaggielipscomb]

How about adding some flashing before attaching the ledger to the rock stemwall?

[oldguywisdom]

The way I've always attached decks is using all thread that goes through the house band board with a washer and nut on the inside. No way the deck can ever pull Away. Lag bolts are ok. I just don't trust them.