3 ms·
There are some modern construction techniques that make me nervous: One is pre-stressed concrete. This has replaced I-beams for highway bridges. The problem
by jhallenworld 11y ago
There are some modern construction techniques that make me nervous:
One is pre-stressed concrete. This has replaced I-beams for highway bridges. The problem here is how do you inspect them? With steel I-beams you can use your eyes. With concrete maybe you need some kind of ultrasound equipment to check the tension cables? Do you trust those responsible for long-term maintenance to do it?
Another is engineered wood I-beams for houses. Basically these are floor joists made out of plywood. How long will they last? What happens if they get wet? If there is a fire the house is gone because the floor joists will be ruined by the water to put the fire out.
There were certainly mistakes in the past as well. One is building with cast-iron beams. They look nice, but they crack.
- Gibbon1 11y agoScuttlebutt I've heard. If a modern stick house built with plywood beams catches fire, the fire department will not try to save it because it's too dangerous to send a man up on the roof to cut access holes. This is because in a fire the glue in built up beams loses strength very quickly and the thing de-laminates.
- nkurz 11y agoIf there is a fire the house is gone because the floor joists will be ruined by the water to put the fire out. Do you have more information on this? I've known about the increased direct risk from fire, but haven't seen anything about damage from temporary water contact. The only information I can find doesn't seem to agree with this, although it doesn't specifically prove otherwise: www.woodbywy.com/document/tb-213
- jhallenworld 11y agoWell I went looking for this and it's not as clear as I first thought. The fire risk is the biggest issue. The webbing for "TJI" is made out of OSB, and it seems there is definitely a long absorption time for this material so I'm thinking the collapse risk from water during firefighting is not all that high. Nobody is recommended ignoring long-term dampness (like from a leak) and the manufacture will certainly void the warranty.