Parallel deck joists

Ok, so I’m celebrating 5 years in the business this month and this is a first for me. Inspected a house where the deck joists run parallel to the foundation. The house is 28 yrs old. Is this possible? My inner instinct says it’s all wrong, but, this is the first time, so maybe there’s something here for me to learn. Has anyone else encountered such a thing?

I am assuming that there is a bay window and a fireplace projection. The deck was framed so as not to put the weight of the deck on the house projections.

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Go with your instincts on this one. It’s all wrong.

DCA6 Prescriptive Residential Wood Deck Construction Guide Based on 2015 IRC (revize.com)

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Hey Scott, there are bay windows, but I would think that putting the correct headers around those fixtures would have been adequate instead of running everything parallel. I found it funny that they still used lag bolts on both the bay window and the chimney box.

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Probably, but it is easy enough to go around them with a built up beam.

That ledger is still load bearing, but now it is pin-pointed. Probably a good reason not to do it. That one point is carrying a lot of weight.
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@kleonard has it right, IMO.

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Exactly, and with the use of nails.

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All wrong. How well supported is that girder where it attaches to the ledger without hangers? Twice as much lumber for less strength. How could that be right?

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None prescriptive construction method, would have to be engineer designed and approved. Have the seller provide this information otherwise defer to SE. BTW, I see no flashing.

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I agree there are many issues here but to answer OP’s main question - joists running parallel to the foundation isn’t inherently wrong. Inefficient and difficult? Sure, in most cases but it all comes down to how the loads ultimately are supported and attached to the house.

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You’re not showing the whole picture, how far does the deck project out.

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Thanks for pointing that out about parallel joist. I just spent an hour researching why it would be improper and could not find anything stating it was. I do agree about proper fasteners, bracing and connections. I’ve seen a number of decks built this way and only a few that looked like the OP’s and yes, I called out my concerns but not about parallel joist.

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Here’s a couple of larger views.

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IMO, there’s the reason for the parallel joists… load-bearing enclosure/roof!

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So, does that mean this is … ok? I don’t have a construction background so I’m a little confused.

Back in the day, the old farmer’s porch was framed parallel to the house.

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Yup, No longer an IRC deck. This has been designed or engineered. (Hopefully). I still have concerns with load points, lack of brackets, lateral bracing etc. I would be happier if it were designed like a free standing deck.

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That’s what stuck out to me when you look at the overall picture. Those end posts should get some cross braces.

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The roof and the stairs are taking care of the lateral bracing.

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I think one reason could be if it’s desired to have the walking surface boards running perpendicular to the house like the old porch Scott posted. Now that I think of it nearly all of the old house front porches in my area are done that way.

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I agree with Kevin… :-1: …Point loads, post to beam connections, ledger attachment to house, etc.

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