NEW YORK ( MainStreet) — "The roof over your head" stands for shelter, a basic human need. But this essential domestic feature could pose a threat to one of the most important financial protections a family can have: according to Insurance.com , some providers are "refusing to renew existing homeowner insurance policies on houses with roofs older than 20 years" without an inspection.

A failed inspection can mean that the roof must be replaced before the policy can be renewed, and some companies won't write new policies for homes with roofs older than 20 years. Others will pay only cash value for an older roof at the time of damage, not the cost of getting a new one. In 2012, Allstate introduced such a policy for roofs older than 10 years in Oklahoma, and the company is said to be expanding it nationwide.

According to Allstate CEO Thomas Wilson , this change is an important part of making home insurance profitable again: "People just don't get their roofs fixed and then a hailstorm comes and we replace a $20,000 roof when we're getting a thousand bucks from the customer and it's obviously not a good trade."

Replacing a roof can of course be a major expense: according to Angie's List , a professional job for a standard 2200-to-2600-square-foot roof can cost between $2,000 and $8,500. (Roofs that are especially high or steep, or made of wooden shakes or metal, are more expensive.) But there isn't an alternative if one's home insurance policy is on the line.

Companies are limiting their liability for roof claims in other ways as well. Some West Coast insurers are restricting coverage for roofs made of wooden shingles or shakes, or excluding them all together. Other companies are limiting appraisal for wind and hail damage after claims are filed, which one Colorado business consultant said "effectively guts the appraisal clause in the policy." That means, according to the consultant," if you have a metal roof and file a claim for hail damage, they may come back and say that the damage wasn't caused by hail but by wear and tear due to age." Another maneuver is designating damage as "cosmetic," and therefore making it the client's responsibility.

Roofs are vulnerable to damage not just because of weather and age, but because many suffer from poor workmanship. One expert quoted by Insurance.com said that the proportion of new roofs that don't meet the specifications for a valid warranty is "in the high 80% range." Homeowners considering roof replacement are advised to be careful when hiring workers: visit the Roof Consultants Institute to find an assessor, or the National Roofing Contractors Association to locate a qualified contractor. Even if you don't spring for a replacement, a written report can help prove to your insurer after a storm that the damage wasn't pre-existing.