Porch repair - minor (I think?) wood rot

[Kashka-Kat]

Phil, I guess the pic isnt very clear - th top of the fascia board is level with the top of the floor boards and a piece of trim or something would be sandwiched over both to bridge the gap. (there was metal flashing covering it before which I took off).

I dunno - Im kinda burnt out on trying to explain it and having people come to look at it and criticize how it was futzed by the previous owners. At this point Im just going to take the advice of the last guy who saw it, who actually was quite knowledgeabout about construction and porches and who looked underneath via the coal chute and inside the gaps and thought that the joists and everything underneath were quite solid and straight and that really bad corner - the two sides that are inside are where the weight is actually resting on something underneath. He said if it was him he'd just go the Abatron route+ polyurethane caulk... and then revisit the whole question in 20 yrs. hahaha its my favorite strategy, just re-define it as a non-problem. Well actually it IS a problem, the rot does need to be corrected and kept from advancing further and everything made completely watertight.... and that corner solidified so it can keep on holding weight. As this guy pointed out, if it costs about 2-3000 to have someone rebuild only that corner maybe it would be better strategy to wait and then do a more extensive rebuild if it needs it then. It may not if further rot is avoided and structurally its solid

Casey I have actually used the swiss cheese method quite successfully on some sills that were pretty bad and they are still holding paint 7 yrs later. I was told by an Abatron rep that when you inject the 2 part liquid wood that it seeps into the fibers a good 1-2 inches so assuming enough holes are drilled it should be pretty solid in the end. Jobs like that suit me, sometimes its advantageous to have a mild case of OCD

Wish I had y'all's ability to take things apart and reassemble but Id have to hire it out Im afraid.

One of the guys told me that Abatron can be considerecd structural - is that true?

Thx all, it helps me to consider and talk thru all angles.

[Casey]

Pic of this mess where they sawed off the rotted floor boards that were sticking out:
20160629_172627.jpg

Text deleted - situation has changed

This is a water trap, and with the 90 deg. change in direction and the associated wood movement, it can never be made watertight. No amount of sealant or caulk or epoxy will have a positive effect/ water can always get into the t&g's further uphill.
You could bridge the horizontal and verticals here with custom-made metal flashing, buried under the wall trim, and that would keep the water out, yet still let moisture that got in further up the slope escale and evaporate. Caulks and sealants also seal in water making it harder to evaporate.
Casey

[Kashka-Kat]

Yes, absolutely, the gap will be bridged and Im thinking thru how the flashing could be tucked behind/underneath walls & trim - will post some pics along the way to make sure Im on the right track -thx.

[phil]

sorry my reply got too wordy.
you can deflect some of the water with flashing and perhaps you can cut some wood that has a taper such to shed water.

I think it's a good point to make about the longevity. Yes it's really just the tip of the iceberg and you might find ways to circumvent the need for a porch rebuild. the most important thing is it isn't getting worse quickly and everyone is safe. and likely there are quick fixes to delay major repairs and since you are looking at hiring out it's more expensive for you.

when working on projects like this try to think of having a party and someone hurts themselves or starts telling a joke and all of a sudden you have the maximum number of people that the deck or room will hold. Now you are in a situation where a catastrophic failure is possible.

The same situation could happen within 30 seconds if someone wants to take a picture and says OK everyone go stand on the stairs, now you could have 20 people on a single staircase.

even though it's probably rare to have the maximum number of people in any area. it's possible and this can easily happen suddenly.

making it safe might involve some blocking that could take the weight should rotted wood fail suddenly. Otherwise the guy might have a good point that the thing might last another 20 years and when you fix it you or another owner rip it all apart, it might not change the cost much.

Maybe it can be delayed so long as it's safe for people and not getting worse rapidly or creating a stinky mess of rotting wood.

I';d say the results of epoxy repairs are structural in the immediate area of the repair. It doesn't' really soak in far unless it can get into cracks. most epoxy repairs are too small to really be a part of the overall structure and if you try to use a lot of epoxy you'll have to consider the price. New wood is cheaper. It can be used in structural repairs but the product itself has very little strength.

think of a boat. All the strength is in the fiberglass, the resin is the glue that holds it together but if you were to build a boat from just glue ( resin) it would be weak as anything. Resin , be it polyester or epoxy has strength as a glue but on it's own it has almost no strength.

my brother called me up because he knows I have some quantity of epoxy. he just bought a fiberglass boat. the transom ( where the motor mounts) is rotted. the fiberglass shell is fine. it's got fiberglass on both sides of the transom but the plywood between is rotted. it's not practical to take the inner and outer sections of the boat apart.

he can drill out all the rotted wood and put little discs of new wood or fiberglass cloth in there and then fill the hull with epoxy. the glue is needed in this case to add the strength but you couldn't just remove the plywood and replace it with glue. he could drill a bunch of holes and stuff lots of absorbent material like fiberglass or wood chips in there and then soak that with the resin. The repair is possible. the amount of epoxy he needs is a factor. its worth about 200 bucks a gallon. he also need something in there for the resin to glue to , some sort of fibers. otherwise if he just filled the transom with resin it wouldn't be strong enough. its not really possible to replace the wood or take it apart but as it is the boat is too weak to be safe. in cases like this epoxy repairs can do a good repair. Most wood, if you can get to it is better just replaced. In this case it might cost him a couple hundred bucks for the epoxy but it may save the boat from the dump. since he has the motor and trailer it's still practical.

[Kashka-Kat]

thx as always Phil - you put a lot of thought into your posts & look at things from various angles. Structurally we are fine, the undersides including all inner joists/framing are just fine, having been protected by porch enclosure for most of the 100 yrs so water really has not been getting under there at all. The entire porch was covered with aluminum siding with only 3 tiny windows for at least 40 years so that was further protection - I dunno, maybe I should have left up that aluminum, it did a good job protecting but too bad it was just so ugly!

The only rot to get the "swiss cheese" abatron treatment are very small areas at bottoms of the 2 OUTSIDE panels of two of the box beam posts (the corner posts) - the worst one shown in the pics. The inner two sides of of these 2 box beam posts are fine, and the other two posts (not corner posts) are completely fine and dont get as much weather hitting them. Still havent found anyone to hire - two guys didnt want to do it (apparently), one I havent heard back from, and one gave me a proposal for $2600 to do basically what I can do for much less - ie just building up/adding trim in such a way to cover the gaps and shed water as much as possible.

As Im looking at this Im now thinking - what the heck, Im going through all this bother, I really should go ahead and just replace the sections of the decking underneath those two corner posts. Im thinking of something that would look like the pic of MJT's porch (link above) that shows that gray panel that goes under the posts. MJT -what did you use for that gray panel? I was thinking Id use cedar but Ive been hearing about these dimensionally stable, waterproof products that supposedly saw and act just like wood.

My only hang up now is - how to support the roof temporarily while I remove & replace the old wood floring strips under each of the 2 posts in question. - NOT that the supports will hold much weight - need only work on one post at a time - and Im thinking I dont need to RAISE it so much as just keep the post from sinking -even just a tiny fraction of an inch would make it hard to get the new wood in. Or maybe I do need to raise it a hair - say 1/2 inch?

Due to space and other considerations, it really would work best if I could use the metal adjustable jacks and have the supports be vertical supports instead of angled but Im not seeing much about how to do that? CAN I do that? Something I read said that the angle of the angled supports has to be such that it takes the forward thrust of the porch roof .... which confused the heck out of me. Obviously I dont know what Im doing! Or the laws of physics for that matter.

I do have some siblings I can and will talk to who would know but any other tips/tricks would be helpful. I find I have to get lots of tidbits from a lot of different sources, like pieces of a jigsaw puzzle.... and only once I have a clear picture in my head of what to do and how it will work , then I'll proceed

thx!!!!

[mjt]

As Im looking at this Im now thinking - what the heck, Im going through all this bother, I really should go ahead and just replace the sections of the decking underneath those two corner posts. Im thinking of something that would look like the pic of MJT's porch (link above) that shows that gray panel that goes under the posts. MJT -what did you use for that gray panel? I was thinking Id use cedar but Ive been hearing about these dimensionally stable, waterproof products that supposedly saw and act just like wood.

In this photo, you can see the post is just hanging free while the supports hold the whole second floor porch up.

If you are referring to this photo, the grey boards are the porch flooring after it had been installed and painted. It's quarter-sawn douglas fir. Those photo is misleading as it's actually green rather than grey... The bottoms of the columns were replaced with treated lumber, cut to the correct finish height. The porch was the jacked up to provide enough clearance to slide them into place and fasten them before lowering the second floor porch down onto them. The bottoms were then wrapped to hide the treated lumber.

[phil]

If you can put a post so it's under where you want support and the bottom is on a piece of plywood in a location where it's got good support and a tad too long to be truly vertical then you can kick the bottom towards upright and this will put lots of upward force on it.
I suggested making an A frame just to be a bit overkill rather than too light. If you just had one post it might be kicked out so you can put some cross braces so it can't fall out. If you can arrange them in the shape of an A this is a strong structure for support. keep them as vertical as you can. the more vertical the sides of the A are , the more upward pressure is put on ( if you kick or hammer the bottom more towards a vertical position.)
until you eventually reach 90 degrees. This is pretty simple leverage.

if it were an A shape then your support can be from the bottom of the two 4x4 so it wouldn't need to be where the post is. tie them together at the bottom so they can't slip out or away from each other. you can kick them towards or away from vertical to adjust the height.

You can rent jacking equipment like in the photo if you need them but I'd just pick up a couple of nice fir 4x4 and use that for your support, You'll find some other use for them after. If you just want to lift you can put the post on top of a car jack but that isn't very stable and you don't want it to be kicked out when you are working under the weight of the roof. You could do that for slight movements but don't take a risk. If you aren't sure any carpenter could probably assist. The deck of your porch might not take much weight so if you need to you can put blocking under the porch deck for safety, so it can't cave in.

Maybe you could dig a hole and put a sonotube underneath to makes a form for a foundation for the post if you can dig there. If you have to use a block a big block of fir would do fine. you might be able to find a piece of heavy plastic so the moisture from the ground won't attack the blocking if you use a block as a foundation. Maybe an old railway tie if the creosote isn't an issue for you. something like a mudflap off an truck can work ok to isolate the dampness from ground. I see them at the sides of the road sometimes and they are ok for this , just nail one to the bottom of your heavy block and put some drainage under there. that'll help because then it can't act like a sponge.

lots of old houses were built on nothing more than blocking that sat on the ground. These days you need a better foundation to pass code but I think it's reasonable to use heavy blocks to support the porch roof if you don't want to go pouring cement. how much you need might depend on a lot of the soil. If it's boggy , then it might not be as good as if you are on rocky soil that is more stable. If you had an inspector in your hair he'd probably want to see you dig a three foot deep hole and then he'd look at the soil and maybe tell you to dig deeper.

make sure you keep the porch deck sloping downward away from the house, don't make it perfectly level, so the rain runs away from the house. No one will notice the slight slope.