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IowaSPEMan
Adding more support in the basement
IowaSPEMan

In my dinning room the floors near the walls are nice and firm but towards the center of the house sink in a little and have some give. The wall show in this photo, however, does not have any support directly beneath it. There is a load bearing beam a feet away.

As a result, over the years the joists have taken a beating and previous owners have sistered the joists to prevent further damage. It seems that this has been an OK fix but the joists they put in didn't span the whole way.

I would also like to frame in some of my basement so that the furnace doesn't draw in as much cold air and so the basement is a little more temperate.

As I think about adding more support, load bearing beams or walls, I am trying to think about where I can add them without having to add more concrete footing. I don't really know what areas of my basement have reinforced footing. Any help on this? The area in most need is the first 3-4 joists from the door into the unfinished area of the basement.

keith3267
Re: Adding more support in the basement
keith3267

Its hard to figure out what you need from your current photos. Try lying on your back directly below the area you want to reinforce and shoot straight up.

As for a footing, you can either dig up the slab and pour one or you might try one of those post supports used for outbuildings, sheds and decks. They are shaped like a pyramid with a 12x12 base, a small taper to an 8x8 top with a 4x4 pocket and two slots for 2x lumber. They are about 8' tall. You can find them at Lowes or Home Depot in the deck area or concrete block area.

dj1
Re: Adding more support in the basement
dj1

What you need to do is to invite a couple of general contractors for evaluation, because we can't see much in these pictures.

But from what I do see:

- Sister joists that are not as long as the original joists, are not effective, like that one I see in the second picture.

- Joist hangers may not be enough with all the "sisterings", and a support beam, perpendicular to the joists and resting on new posts, may be needed. Steel beam could be used here.

Get at least two GCs and tell us what they said.

IowaSPEMan
Re: Adding more support in the basement
IowaSPEMan

Keith, here are those photos you requested. They go from right to left. Thank you so much.

dj1
Re: Adding more support in the basement
dj1

In the first photo (of the new ones) I think I see a metal beam going across the joists. You will need to add another one like it where the sag is the worst.

In the third photo I see one rotten joist.

I still say: get it inspected.

keith3267
Re: Adding more support in the basement
keith3267

That floor has been butchered up pretty bad, Its hard to see exactly what has been done and what needs to be done because of all the clutter. Pretty much, you need a continuous beam from one support to another. Anytime you have to cut one of those beams, you have to sister the beams on each side, continuously from one support to the other, then you can cut the beam and add the cross pieces and secure the ends of the cut beam to the cross pieces.

There needs to be two sistered continuous beams under the wall above, no cuts allowed.

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