Siding Inspections for LP or Hardboard Siding in NW Washington

large house siding inspection

Hardboard or Composite wood sidings are made from various combinations of wood veneers, fibers or flakes, bound together with glues, resins, and/or waxes. They come with different names, LP siding, T-11,  Plywood, oriented strand board (OSB), and hardboard are basic engineered wood siding materials. Several different types and brands of engineered wood siding have experienced moisture-related failures due to product or installation defects, or improper maintenance. For the purpose of this article we will refer to these products as composite siding. Generally speaking homeowners with siding installed after 1996 will have fewer problems than those installed prior to that. There have been many class action suits against the manufacturers of earlier product. For many homeowners, the time has passed to receive any compensation from the class action suits however most of the composite products did have a warranty and manufacturers such as Louisiana Pacific are paying warranty claims. While Louisiana Pacific (LP) was the most publicized there were many other companies who also made this type of siding.

Siding, manufactured from oriented strand board and other wood composites, have the advantage of being manufactured from relatively low cost wood and young trees, thus saving money and attempting at a more benign impact on the environment. Such siding products became more attractive as traditional wood siding decreased in quality and/or increases in cost. Unfortunately, most of the experience with such siding products have been poor. Most of these products have experienced moisture related problems. Many homes in the NW Washington have been sided with composite or OSB siding. These products have  been problematic  in the NW Washington due to lack of maintenance, the weather and moisture conditions.

Locally Used Manufacturers

Other Manufacturers

We have limited information on other manufacturers mainly because we do not see their product often in this part of the country.

Fiber-cement Products

Fiber-cement siding has the look of wood siding but has a lower cost and lower maintenance. Market share is approaching ten percent, according to manufacturers. Most newly constructed homes with lap siding with have this type of siding. Additional benefits include resistance to termites and fire. Fiber-cement siding will not rot, buckle or warp and holds paint for several years longer than conventional wood siding. Moisture resistance is a concern, but problems can be avoided if the siding is installed correctly and properly treated.

Listed below are a few of the most common installation defects that I find.  The funny thing about these installation defects is that the installation instructions are very clear and very specific – the diagrams below all come directly from James Hardie.  The other manufacturers of fiber cement siding have nearly identical installation instructions.

Improper Clearances

  • Must be kept 2″ away from roof surfaces, decks, driveways, steps, and other similar hard surfaces.
  • Must be kept 6″ above the finished grade.
  • Gutters must be kept 1″ away from the siding, and kickout flashing needs to be installed.
  • Must be kept 1/4″ above flashing above windows, and not caulked at the z flashing

Improperly Attached

  • Must be blind nailed or face nailed, but not both.
  • The proper size nails must be used (6d or siding nails).
  • The nails must be driven in straight, and must not be over-driven or under-driven.

Not sure what you have? Siding Solutions Identification page

Composite Siding Maintenance

Some of the pre 1996 versions of the LP and similar siding products failed soon after installation. Later versions have lasted longer but as of the fall of 2004, we have yet to see such a product that stands up in our wet Pacific Northwest Climate unless it is vigilantly maintained. The most common conditions which seems to warrant some “preventative” maintenance and eventual replacement are: limited swelling and thin cracks along the bottom edge of the siding. See the first picture below for an example of this condition

Regular application of a good quality exterior paint is critical to successfully maintaining composite siding. Although one would expect the area painter to know the areas of composite siding that needs special attention, we have seen enough poor applied or sloppy paint jobs that a gentle reminder is in order. Make sure that all joints are caulked and that paint is sprayed up into the overlaps of the siding. Many painter tend to spray “straight ahead” however the areas that really need the paint are the bottom edges and directly behind the bottom edge. See the pictures below for examples.

Other maintenance practices:

  • quality caulking of any dimpled nail heads, abuttment joints, any areas where water may sit or pool and around fixtures such as lights or hose bibs
  • priming with Parker “Flex Bind”, Pittsburgh “Permenizer Plus”, or similar primer material. Note: brushing the primer into the bottom edge of the siding is a critical element of this work.
  • keeping vegetation, soil, roof drainage and sprinkler water off the siding.
  • make sure sheathing has at least 1/2″ clearance where to roof and side walls of the home join together. These joints are normally covered by trim and not exposed.

Painting is unlikely to solve all of the problems with this type of siding or help with severely deteriorated material but it should prolong the life of the product.

Examples of Siding issues

Should I buy a home with LP or any other composite siding?

First, not all composite siding is bad. Initially I would qualify the age. If it was manufactured prior 1998 it may be first generation products which had a higher rate of failure. to If there are any signs of the composite siding failing, we advise getting it evaluated before purchasing a home. Why? When you buy the home the siding issues are now yours to deal with! It takes your time and your money, once you own the home. In most areas like the Pacific Northwest, composite siding has a finite lifespan like a roof does. It takes meticulous maintenance of the siding to extend its life beyond twenty years. This is the “short answer” to “should I buy a home with lp siding on it.” As with all things it’s entirely your call, well unless you are getting financing.

The Short Answers:

Should I buy a home with LP siding on it if I’m paying cash? I wouldn’t, unless you own a siding company or have the repair costs deducted and have some spare time on your hands. Get the lp siding issues fixed first.
Should I buy a home with LP siding on it if I’m getting financing? You may not have a choice. If there are any signs of LP Siding rot, delamination or failing the chances of passing inspection are very slim. And if the home fails inspection for LP Siding issues many lending companies will not approve your financing – hence you may not have a choice.

I have failing Composite Siding, what should I do?

The Short Answer: the sooner you get it fixed the better.
If your LP Siding is already showing signs of rot, delaminating, fungus, mold, swelling, mushrooms or separation – it’s just a matter of time before you have a real problem on your hands. Your first step should be to get a unbiased opinion on the extent of the damage. You may want to call a contractor but remember they are in the business of replacing siding and can be biased. You will be better off with a certified siding inspector such as Pacific Crest Inspections. We can gauge the extend of the damage using industry guidelines to determine the extent of the repairs needed.

Stabilize
In many cases the deterioration has begun and but still within the industry guidelines so replacement isn’t warranted, yet. Your best bet is to stabilize by cleaning, re-caulking and painting the siding. You may still end up replacing the siding but can postpone that investment by aggressively maintaining it.

Replacement
Most siding companies pull off all of the LP lap product and install new hardi-plank, vinyl or cedar. However, some siding companies re-side over the LP panel siding instead of pulling the panel material off. This process can have cost benefits; but, prior to siding over the panels you should look to see how much damage there is to the panels. If the damage is too severe, we do not suggest siding over the panels. Additionally, in many cases we do not suggest siding over the panels with vinyl.

Most builders placed either OSB or plywood behind the “Lap Siding”. So, if you take off a piece of lap siding you have another protective layer of material before you get to the cavity of your wall. The panel siding is what we call a “single wall construction” type product.

If you pull off a piece of panel siding it will immediately open up the cavity of your wall. You will be able to see your wiring, insulation, plumbing etc. This is one of the reasons so many siders suggest siding over the panel siding. By siding over the panel siding it gives you a second layer of protection. Thus the terms… “single wall construction” (panels only) and “double wall construction” (lap siding followed by a layer of plywood or chipboard). We do not suggest that you side over any panels that are seriously damaged. Usually the most damaged panels can be found in the non-insulated areas of your fireplace chimney or over the garage entrance. Chipboard products are often called “OSB” – oriented strand board.

Some siding companies claim that you cannot put vinyl over hardboard siding, not true according the the National Association of Home Builders.

Liquid vinyl siding – the answer to your siding problems???

Liquid vinyl siding problems are recent, since liquid vinyl is a relatively new exterior coating. Unlike vinyl siding, liquid vinyl is a spray-on, viscous coating that can be applied to any paintable surface. It dries to the touch in minutes, but requires about three weeks to set. However if you hardboard siding is damaged or moisture laden, liquid vinyl may not adhere and properly protect your siding

As with any exterior vinyl product, whether siding or coating, the surface to be covered must be in perfect condition. Preparation of the surface, and installation, are critical to the prevention of problems. Moisture has been the central issue in siding products, and that leads back to proper treatment of the substrate and installation that meets known standards for liquid vinyl.

Installation instructions for liquid vinyl are well-known, but not always followed. Any underlying mildew, dry rot, or mold must be removed from the substrate. If necessary, any defective area must be replaced. No imperfection in stucco or wood can be overlooked. If faulty installation leads to future problems with moisture, mold lawsuits will be among the litigation that follows.

After sanding, caulking, and scraping, a primer is applied that is a bonding agent. Last comes the liquid vinyl coating. This elastic, water-resistant coating is a breathable film that eliminates moisture, and is guaranteed for 50 years. If, however, preparation of the substrate and actual construction standards are not maintained, moisture-related liquid vinyl siding problems can develop and building product lawsuits will result.

Many of the companies who install this product are subcontractors or independent companies and their experience will vary. Ask how many times they have applied this product and what issues they have seen.  I would always do a check with the Better Business Bureau and ask for at least three reference customers to talk to.

Ask The Builder article on liquid siding