Why might an underwriter be concerned with a Flat Roof?

Answer 1

Flat roofs are like Swimming Pools, water collect on/in them and if they leak this water ends up in the house.

Flat roofs are great if you live in hot dry climates where they are great places to put the beds and sleep if you want to be cool at night, but in temperate, wet climates they are very high maintenance and will thus be of concern when you want to purchase insurance.

MAJOR 3rd PARTY EDIT: I am not sure when the above question was asked and answered but it is totally outdated. Up until this century flat roofs were problematic because of the materials used and/or faulty construction. (Aside: Roofers are a strange breed!). Today there is no excuse. There are continuous membrane, foam, elastomeric coating, and adhesive systems that match the best "lifetime" shingle systems and have the added advantage, with maintenance coatings, of extending the useful life of the flat roof indefinitely, if not forever. The roof structure can also be greatly improved by dual (cross-directional) layers of 6" or 8" (or taller) joist beams. This extra layer, besides allowing for more insulation, simplifies the running of electrical and HVAC systems (way fewer holes to be drilled for conduits and eliminates using interior space for such runs). The extra layer may require beefier wall studding but a thicker wall cavity can be used to your advantage by allowing thicker insulation, deeper window sills, and reduction of continuous contact area between the outside and inside surfaces by staggering the wall studs. Throw a "mansard": (sloping, partial, side roof) (solar?) into the mix and you can forget about gutters, cleaning gutters, freeze-thaw ice/water build up/intrusion in/from gutters, and replacing gutters!!! For reader information: I am a flat roof homeowner (the house, not me) since 1980 in Washington state. The original roof leaked after about 6 years (and one year after we bought it secondhand). We had it replaced with the same hot tar ("built up") material but, luckily, learned about coatings, starting with fibered aluminum, then elastomerics, then ceramic elastomerics, and then back to elastomerics. Thirty-plus years later our coated 20th century material looks like it is a couple years old: no alligatoring, no leaks, no snow removal (up to two feet), and no gutters(!!!). BUT it has taken a lot of frequent and expensive maintenance. This is due to the fact that were doing all this in the transition period when technically advanced flat roof systems were becoming more available (we had seven roofers bid on our initial problem and none mentioned anything but BUR). Even with the better elastomeric coatings I still have to visually check out the roof every 2-3 years for hairline cracks or thinning of the coating. I have had to do one major replacement of the coating layer over the shower/bath room but this was more than twenty five years into our replacement roof. In short: No reason to fear a modern flat roof residence if you confirm the quality of materials and construction. And, you can walk on your roof without mountain climbing gear! There is a slight kink in the works: INSURANCE COMPANIES. Since Hurricane Katrina some insurance companies have, without supporting empirical independent studies, taken the view that flat roof houses are riskier (and more premium worthy) and some of these companies refuse to insure them. I understand that this trend may have begun even earlier in the UK, possibly prompted by the predominance of "eons" old flat roof residential structures and close proximities. Even if this trend is just another example of insurers inventing an "added" risk for the purpose of revenue enhancement (i.e. gouging), it is a reality and most state insurance commissioners currently allow the companies to "choose their risks" rather than requiring that their choices be evidence based. There are still respectable (and competitive) insurers, even in states like Washington that refuse to reasonably regulate such unilateral decisions, that continue to insure flat roof residences. Hope this (somewhat) wordy blurb is of some consolation to flat roof homeowners, and prospective flat roof home buyers, and potential flat roof home builders, if not actual help.