Roofing Felt Isn’t Always Necessary When Using Shingles


Question: The home we’re buying has two layers of composition shingles, and the seller assures us that the new layer is only 1 year old. When the home inspector checked the roof, he found that the new shingles were installed without a layer of felt. He also found a water stain on the living room ceiling and recommended that the roof be stripped and replaced with new shingles. The seller says these water stains occurred before the new roof was installed, but the inspector believes the lack of felt is a serious roof defect. Who should we believe? Is felt really that important, and what is roofing felt anyway?

Answer: Roofing felt is a layer of tar paper installed beneath the shingles to provide a backup waterproof membrane in case of leakage.

Felt, otherwise known as underpayment, is required when asphalt shingles are installed as a first layer of roofing or when they are applied over wood shingles or a built-up roof.


Some contractors and home inspectors believe underpayment is required when second or third layers of asphalt shingles are installed, but there is no basis for this opinion in the Uniform Building Code. In these instances, the felt beneath the older shingles is regarded as adequate.

As to the ceiling stain in the living room, this may have occurred prior to installing the new shingles. If you have serious doubts about the integrity of the new roof, a second opinion should be obtained from a licensed roofing contractor.

But don’t let the lack of underpayment become a major issue for you, because it is simply not required for a second layer of composition shingles.

Blame Lack of Venting for Rotted Framing

Q: Now that I’m selling my house, a home inspector has discovered major water problems beneath the building. The ground, it seems, is very muddy, with small puddles in various places.

Worse yet, droplets of water are hanging from the floor joists, and this has apparently rotted the framing. I checked under my neighbor’s house to see if he had the same problem. His soil was also wet, but there was no water on his floor framing. What could be the source of water on the wood structure?

A: The water on your floor framing is vapor condensation, indicating a lack of adequate ventilation below your house.

Excessive ground moisture is common in some neighborhoods, most often the result of geological conditions and subsurface drainage. This typically occurs during and after heavy rains, but over-watering of landscaping can sometimes make it a year-round event.

In most cases, as with your neighbor’s home, ground moisture below a building does not pose a serious problem. When sufficient ventilation is lacking, serious damage can result.

The building code requires cross ventilation of crawl spaces below dwellings, with vent openings equal to at least one square foot for each 150 square feet of floor area.

When sufficient venting is not provided, the alternative requirement is to cover the ground with a plastic membrane. To ensure proper ventilation, a licensed general contractor should review your home.

However, since you also have rotted framing, the structure should be thoroughly evaluated by a licensed pest control operator (commonly known as a termite inspector).

Inspections Are Smart, But Not Mandatory

Q: I purchased my home one year ago, but no one advised me to have a home inspection. As a result, a lot of problems became apparent after I closed escrow. It is now my understanding that a home inspection is mandatory with every home sale. What can you tell me about this requirement?

A: In most states, including California, it is required that sellers and real estate agents disclose defective conditions of which they are aware.

But you are misinformed regarding the relationship between mandatory disclosure and home inspection.

To date, there is no requirement specifying a home inspection when a property is sold. Home inspection is an optional service, available to buyers upon request.

Most real estate agents make it a practice to strongly recommend an inspection, but unfortunately, some buyers remain unaware of this essential service or simply choose to take their chances without one. Consequently, a surprising number of homes still close escrow without adequate disclosure of physical defects.

Shingles Show Signs of Premature Age

Q: The buyers of our home hired a home inspector. According to the report, the edges of our roof shingles are curling. This comes as a total surprise, because the shingles are only 5 years old. How could this roof be wearing out so soon?

A: Curling can result from substandard manufacture of the shingles, but the more common cause is inadequate ventilation of the attic. With insufficient venting, an attic can become very hot during summer months, causing asphalt shingles to become dry and brittle after several years of exposure.

Code requirements for attic venting are minimal at best, and municipal building inspectors have the discretionary power to waive these requirements at the time of construction.

With prematurely aged shingles, your first step is to inspect the attic vents, typically found at the gables, the eaves or on the roof itself. To ensure that they are clear of obstruction, look for visible light in the attic. Eave vents often become blocked with insulation, and low clearance within the attic can restrict your ability to clear them.

If additional vents are needed, they are not difficult to install. An effective way to meet and exceed current ventilation requirements is to install turbine vents near the roof ridge. For further details and specific evaluation of your roof situation, contact a licensed roofing contractor.

Fireplace Without a Liner Is a Hazard

Q: Three years ago, we installed a steel insert in our brick fireplace. It has been an excellent heat source and has given us no trouble. But last week, a home inspector described the insert as a fire hazard because it has no chimney liner. The cost of installing a liner is nearly $1,600. Is this repair really necessary, or are other solutions available?

A: The main problem with most fireplace inserts is that homeowners or handymen install them, rather than qualified technicians.

When lay people perform their own installations, they often take the word “insert” too literally and merely inject the fixture into the firebox, as though it were a cassette, not realizing that the lack of a chimney liner can pose a major fire hazard.

Without a liner, functional problems are rarely apparent, giving the false impression that all is well. But with each repeated use, dangerous conditions are gradually taking shape behind the scenes.

When no liner is installed, smoke fills the space between the insert and the firebrick lining, rather than rising directly up the chimney. As these vapors pervade the cavity behind the insert, they become relatively cool, allowing creosote to accumulate on brick and metal surfaces. This ash-like substance is highly combustible. If the creosote becomes hot enough to ignite, the explosive force of the expanding gases can literally catapult your fireplace insert across the living room.

The best way to prevent an accident of this magnitude is to install an approved metal liner to channel the smoke directly to the top of the chimney. Although the cost of installation may seem high, the expense is more than justified, given the potential consequences of an improperly installed insert.

Wood-Burning Stove Could Be Time Bomb

Q: Last week, we found buyers for our home, but an item that was reported by their home inspector now poses a problem. Our wood stove, it seems, is too close to the wall paneling. I explained to the inspector that it’s been that way for more than seven years, and we’ve never had a fire problem. As far as I’m concerned, if it isn’t broken, why fix it? What do you say?

A: If we were discussing an old fence post, loose door hardware or a drippy faucet, I would agree that there is no urgent need to fix it.

But when the issue involves fire safety, the more appropriate cliche would be “don’t play with matches, or you might get burned.” To put it more bluntly, by the time it’s broken, it may be too late to fix it.

The fact is, your situation may be a slow time bomb. The wall surfaces near your wood stove have been heated and reheated numerous times over the last seven years.

This involves a process called “pyrophoric action,” whereby the kindling temperature of wood is gradually lowered each time the material is heated. The fact that you haven’t had a fire is no guarantee that you or your buyers never will.

I strongly advise that you check the manufacturer’s label on your wood stove to determine the required clearances. UL-listed fireplaces have placards stating this information.

If no clearance data are listed on the fixture, have it checked by a certified chimney sweep. The minimum wall clearance for an unlisted wood stove is 36 inches, unless approved wall protection is installed.

The importance of maintaining proper clearances for your stove cannot be overemphasized. It could save your home and possibly a few lives.