Material choice, blocking crawl space openings

Not a topic I know anything about, but the crawl space is what caught my attention, and then I wrote a whole novel.

My grandparents' house was all built at once but it had a full height basement only under half of it and a shallow crawl space under the rest. So short I think one couldn't even go on hands and knees or maybe barely. . Built in 1910. But I know my gp's didn't move to the north side until my mother was 16 or more, 1924+. After my gp's died or moved, by 1962, the new owner found a target range in that half! I can't imaginek my grandparents created or used it, so it would have been whoever preceded them. The bullseye targets were at the front of the house/crawl space and shooters could stand in the main basement.

The owners, Black fwiw for those who say that Black people don't take care of their property, have fixed it up a lot since my gp's lived there, adding a 2nd bathroom, finishing the rest of the attic for a second bedroom up there, total of 4 (It had only one bedroom in the attic before, with no floor or ceiling in most of the rest of it.), adding AC, painting the outside better, and they've done a lot with the yard too, including redoing the wall and putting in the driveway on the left and a big flower garden. I've been there twice, met the owner, since it was sold but the last time was 1974, so this is just what I can see from the listing.

This has interior pictures!! Beautifully refinished hardwood floors in the living, dining, and bed rooms, totally redone fireplace, new windows in the sunroom and probably everywhere, totally redone kitchen with pass-thru from the dining room. It says: " Ceilings on the first floor are 10 feet, all of the crown molding, panel doors, some with glass knobs, original hardwoods, original door and window mold, beautiful masonry fireplace, all new windows, HVAC 2014, water heater 2015, some newer electrical and plumbing, fantastic potential! This would be a quick turn around for an investor, as much is already done, property sold as-is. " This sounds like it's for sale but it's not. I didn't know it had all this stuff because my grandmother didn't have a lot of lights. The living room was always dark! LOL

They used to have a big pile of bricks in the back, next to the wall next to the alley, 5' high at one end, 1' high at the other end, and 20' long x 3 bricks deep. 900 bricks at least. I think the builder put them there and was going to come back and get them when he built another house, but never came back. They took up quite a bit of space. i wonder if they are still there. (Street view seems to say no.)

LP SmartSide. Comes in 4 x 8 panels, primed. Looks similar to T1-11 in the pictures, but it's not plywood. It's an engineered wood product, treated for resistance to weather and insects. The texture is pressed into the face of the material during the manufacturing process. Paints up nicely. Commonly used as siding for sheds.

The reason for the rotting OSB is the presence of water (dampness in this case most likely). OSB was the wrong choice to begin with anyway, but that aside, PT plywood would work here or LP Smartside as mentioned in another thread. Along with this, I would check for proper ventilation because even with a material that wont rot, the presence of moisture could provide an opportunity for mold growth. Check to see how water got to the OSB and eliminate that water source if you can. If you can', be sure to have sufficient ventilation so that any water that does appear will eveaporate quickly.

Dan

I have improved crawl space ventilation and slightly improved drainage, as much as I could. It is dry underneath but gets some rain splash outside.

Would an engineered wood be better than a cement board like Hardy board?

I was 10 when we bought a new house. The only entrance to the crawl space was a trap door in the family room closet. Had to pry it out, no handles.

I was the smallest so I was assigned to investigate. Mud 2" deep, drying but by no means dry. I had sense enough to look aroudn but not walk around. Still dragged a bunch of mud on my shoes when I came out. We never went down there again.

Later, looking at a map** of Indianapolis, I saw there was a stream through my n'hood, passing through someone's yard only 3 doors down (300 feet total). I went down there looking for it, but only found a back yard that was almost a swamp. Indiana, so the land was flat, and I guess the same water table that ruined his back yard was what made mud in our crawl space. One 15x15' food corner of the yard was also swampy for a couple months in the spring. The self-propelled push lawnmower would leave ruts in the dirt.

**This was a gas station map, maybe Shell. It clearly showed the stream, but I doubt the owner of that house had thought to look at the map. Now, google maps, which normally shows streams, has no indication of it, but I'll bet his back yard is still soaking, maybe the front yard too, and I'll bet what was once our crawlspace is soaking/muddy.