Your Questions Answered
At Ashlar, I firmly b that an educated home buyer or seller is best equipped to make their own decisions. That’s why I take time out of my day each and every day to answer someone’s real estate question. And, when I think the answer can be useful to you as well, I share it here. So without further ado:
Simple answer is because no one wants or could afford mass produced hurricane proof homes.
Dome houses kinda suck from a usability, furniture and floor plan perspective, and the roofing / waterproofing is also a lot tougher than a traditional roof.. so much so that touring dome homes it unusual NOT to see significant water intrusion if it’s over say 30 years. Lot of compromises most homeowners don’t want to make when there are easier and cheaper options.
Plus, building codes have changed… including recently. St PEte for example requires permits for all front door replacements to make sure they are impact and anchored properly, and they also have codes on window replacement… if you replace more than some percentage of the total openings, then you have to replace all of them and they have to be impact rated or shutters provided.
So the compromise is a balance of:
ease of building – plenty of carpenters, roofer and framers that can handle it, no special handling needed like bolts, rivets, steel working, welding, for steel buildings.
cost – low costs almost always gets better demand. extremely expensive homes, such as a steel home, is going to be much more expensive than block and trusses.
safety – there’s things you can do to block and truss homes to make them more wind resistant, and this is incentivised by insurance companies offering discounts to homeowners insurance based on Wind Mitigation measure present in the home. The easiest and quickest mitigation is to install hurricane straps with 3 nails (used to be 2 nails in the early 2000s… there’s another code update for you) with save you $800 – $3000 per year on your insurance, for about $300 in materials. You also get credits for impact windows, doors, garage doors, but that adds up to $25k – $45k so ROI is a lot longer on those.
What you need to understand is that a home is a system of components that work together to keep it up. A roof will 100% tear off of a steel home and a dome will leak like a sieve if not designed properly, installed with expertise and maintained long term.
With block and truss homes the weak point with wind is primarily where the roof attaches to the top of the wall. Historically (pre andrew) it was just toenailed, which is fine for typical circumstances but is terrible when wind is lifting UP on the roof… it essentially levers the roof off the home. Straps and clips resist that upwards force, which is why they are so effective.