Tim's kitchen reno

[mibagent_x]

I am finally doing a reno on my kitchen, long over due. The space is 18x12 L shaped. I have 2x8 unknown grade joists, I believe CX has IDed as yellow pine once before. 16in on center and about 12ft unsupported span. The existing subfloor is 3/4 planks ran at 90s from the joists. And god only knows how many floors stacked on top of that. I know the sub needs to come up and be replaced.

All the info on the joists gives me an L/302. If I bump up to 3in joists I'm good for ceramic. Which brings me to my first question. To sister the joists does the sister need to go from rim joist to beam? Access is thru a crawl space that is definitely a crawl space, so its tight. Getting full length 2x8s would be a challenge.

Second question. Would it be better to run a beam under the joists? Would pre cast elephant feet work for the base of the supports? And what size beam, 4x4, 6x6?

Third question. My parents had a bath redone a while back and the handy man that did it used cork as a thermal break, the bath was on a concrete slab. The cork looked like plain old cork from a bulletin board. Does it really work and could I use it on my project the keep the tile warmer in winter without putting in a tile warmer?

[cx]

Welcome back, Tim.

Don't think CX ever opined upon the species of your joists. And do we know that the joists under this room are the same as those under your living room?

Seems the joists under the kitchen were longer back then, too.

1. When sistering floor joists for the purpose of reducing design deflection you must sister at least the center two thirds of the joist to do any good.

2. Might be. Can't help you decide which is more cost or labor effective without a lot more information.

3. There is cork that is made for the application. Can't say whether your guy used the right stuff or not.

My opinion; worth price charged.

[mibagent_x]

The boards look similar but will put up some pics tonight. This side of the house the span is shorter. There is a cold air return that's framed in and supported. And the other side was a estimate from above. I crawled up with a tape to measure these.

Looking and thinking more about access I think supporting mid span is my best option. As far as ease and cost. What size beam would I need?

[cx]

Need at least some sort of drawing of what you've got to help with the support beam at all.

[mibagent_x]

Ok here are pics of the joists and a layout sketch. No grief on the sketch I am no graphic designer. And it is not to scale.

[mibagent_x]

Nobody gonna take a stab at what size beam I need to use? 4x4, 6x6, 2 spiked 2x10s something else? Or am I missing some important info?

[cx]

Can't tell much from the photo, Tim. Can you get us a little wider view, preferably with a few of the joists?

That appears to be two pieces in your photo? With something attached to the bottom?

1. Where do you plan to put your support beam?

2. What have you below this floor to support your beam?

[mibagent_x]

The joist is solid one piece. That particular joist is part of a cold air return. They took flashing and turned the space between 2 joists into a branch of the cold return. I think the color change you see is where they either cleaned the joist or there was once cloth tape that has since fallen off. The crawl space is dirt with a vapor barrier. I have yet to see any grade stamps, the house was built in the 50s.

I can put the extra support where ever it will help the most but I was thinking mid span. I just need to raise two water lines. I will get you some better pics tonight.

Also the beam length needs to be split in half. I do not have the room to handle a 18 plus foot support.

[mibagent_x]

Here are some wider pics.