Answers to Your Siding Questions #1 Answers to Your Siding Questions #1

Q. For one of my first steps in my exterior paint prep, I will be power washing. My local rental places have equipment ranging from 1000-4000 psi. My house is two stories and about 1500 square feet. The current exterior paint is in poor condition. Which power washer would you recommend? About how long do I need it for? How do I power wash for this purpose?

A. Rent one with at least 2400 psi, but probably not over three thousand since you have never used one before. You will most likely need it for a day or maybe a half-day. You have to try to remove as much flaking, chipping, and loose paint as possible without gouging the wood. The trick is getting used to the pressure as it delivers water and how close you can get to the wood. If you have wood siding, try not to spray underneath as you can shoot water behind the boards. Start out with a 25-degree tip and see how that works for you. The smaller the tip, the more intense the pressure from the spray is. Start out with the larger tip until you get the feel and then move to a smaller tip, as you are more comfortable. Spray from a side angle, remove the chips and flakes, then switch to the other side, and hit it from that angle. Angle the wand slightly downward or parallel to the wood when you spray. It just takes a little practice, but it is not difficult. After you are done, give it at least a good day or so to dry before you scrape.

Pressure washers are not perfect and more than likely, you will have to do some hand scraping. However, do not scrape when the wood is still wet. Do not prime until the moisture level of the wood is less than 15 percent. Depending on your climate, this may be two or three days or a week.

If you are not going to rent scaffolding, do not rent a pressure washer. Your house is two stories high, and you cannot pressure wash that high without scaffolding or possibly a very long extension to the wand. That is backbreaking. Note: You do not want to pressure wash from a ladder - very dangerous.

Q. Some of the homes in my development have mildew on the siding. The homeowners association says they will clean it next year when they have the funds available. Does leaving the mildew cause any health risks to the community or individuals, or any damage to the homes? I know that mold can be dangerous and destructive to both people and buildings. Is mildew a form of mold, and can similar results be expected?

A. Mildew will cause staining to the exterior, but presents no health risk. You can remove the mildew with a mixture of bleach 25 percent in water with a dash of detergent. Wet the surface, spray on the solution and let it sit for five minutes then hose it off. Protect plants from damage by wetting them beforehand and rinsing them afterwards.

Q. I just bought a house that has wood siding. The termite inspector and the appraiser told me that the panels had dry rot. Then other people that have looked at it tell me that it is just a thick layer of varnish and a top layer of paint over the wood that is cracking. How can I make sure if it is salvageable or not? If it is salvageable, what is the best way to go about removing the layers of old paint and varnish without defacing the wood?

A. Dry rot will present itself as a soft part of the wood. Stick a nail into it by hand. If the nail goes in easily, it is dry rot. Cracking paint over sound wood will be too hard to insert a nail by hand. Dry rot will crumble. Dry rotted wood will need replacement.
Generally, exterior paint is sanded or scraped to remove failed paint. Stripping the exterior of a wood house would be a prodigious task. Cracking paint is usually alligatoring, caused by paint either being applied too thickly or drying too fast.

Q. Can vinyl siding, be painted and if so what product and process should be used?

A. You can paint vinyl siding so long as it is not painted a color darker than its original color. Prime with Zinsser 123 and paint with a top quality exterior latex paint.

Q. I have decided to replace the vinyl siding on my 120-year-old frame home with Alcoa Structure vinyl siding. This siding has Styrofoam bonded to the vinyl. Do I need to use house wrap under this siding?

A. You cannot use foam products in conjunction with house wrap. House wrap is not to be used in a remodeling application. The correct answer is no house wrap if exterior foam insulation will be used.

Q. I have existing wood lap siding on a thirty year old home. I don't know for sure, but when remodeling the inside, it appeared as if there was just a black insulation type board between the studs and the siding. I am concerned about ripping the old siding off and then having to plywood the entire house. Is it okay to just add vinyl siding over that existing siding?

A. Yes, you can install vinyl siding over the existing wood siding.

Q. We're looking at buying a house that has brown stained siding, which after 20 years is showing its age. The siding itself seems to be in good shape, although a couple pieces need replacement. What is necessary to paint this? Should it be primed first? Sanded?

A. You can paint over latex or oil stain using latex paint with no special preparation provided that if the original stain was oil based. A sufficient amount of time has passed, about two-three years or so, that most of the oil base of the stain has dissipated. You can use a base primer before painting and no sanding is required unless you need to wood patch some areas. In any event, the surface must be clean and mechanically sound prior to priming and painting. You can use oil or latex paint, as you prefer.

Make sure all the loose nails have been set, the needed caulking completed, and damaged wood replaced. Wash the house with bleach 25 percent in water with some detergent to remove any mildew. Once dry, prime the house if there will be a big change in color or to prepare bare wood. Primer can be tinted toward the final color to aid in covering the old color, is cheaper than paint, and provides an excellent surface for the bonding of paint. Two finish coats will provide greater durability than by one.

Q. When I remodeled my kitchen, I had to board up a window. I framed it, and put two layers of OSB board on the exterior to bring it flush with existing material under the insulation and vinyl siding then covered it with roofing felt. This is okay, temporarily, but I know I need to fix it by adding insulation and siding. What is the best way to go about adding siding to a rectangular area? Should I just work on that area, or pull pieces off and run the siding to the corner of the house? I am thinking of pulling some siding off a side of the house that is seldom seen and patching with that. I think that way when I get new siding to put up, I will put it up in an area no one ever sees so it won't stand out too much. There is an exhaust vent from the micro hood coming out of the area that needs new siding. What's the best way to work around that? I was thinking of making a small "surround" around it.

A. It seems that you have it all covered. Working off a section that is rarely seen seems to be a good idea. You can buy a vinyl-venting block at a home improvement store that is made for that exactly. The vent will protrude from the block and you can run vinyl around the block. Your idea to continue siding to the wall end is good. Additionally, you should stagger the other end joints. This will be more work but worth the results.

Q. Part of my house is sided with wood siding. Whoever installed the siding apparently didn't use galvanized nails, so the nails are starting to rot. I can't really afford to replace this siding at this time, but was wondering if putting latex caulk on the nails would help keep the nails from rotting even more, and preserving the siding until I can replace it. Will this work, or am I wasting my time?

A. Just set the nail; apply a dab of exterior, acrylic, latex caulk; prime; and paint. This will not stop the rusting, but it will stop the staining of the painted surface. Renailing near the rusted nail will provide new support for the board.

Q. I am looking to buy a home that was built in 2002. Most of the home is sided with brick, but at the top half of the rear they used Masonite siding. I've found some bad stuff about Masonite on the web, but can anyone give me your interpretation of what I may be getting in to?

A. It is a no-no. Building code says no way. The code goes back since 1995, because water would get into it and will need to be replaced. If the price is right, you can for sure just replace it. Alternatively, go over it with vinyl siding. Try to get a deal to cover the replacement cost of the siding.

Q. At some point, I read that Tyvek house wrap should not be used directly under cedar shingle siding. Is this true? Someone mentioned that Dupont knew this was a problem and invalidates the Tyvek warranty in this application. I am in the process of adding 1,000 sq ft to my house and we are putting up red cedar siding. I would like to get clarification before I go to him with my concerns. What are the facts that you all have about this problem, and if it's true about Tyvek, where can I find a copy of the Tyvek warranty that states this invalidation of the warranty? It's not too late to put up tar paper, if that is what is called for?

A. Tyvek can be used under any cladding including brick, stucco, vinyl, cedar siding, and stone. Proper installation under each cladding is essential to ensure Tyvek provides the maximum level of air infiltration resistance and bulk water holdout. Major concerns are the proper installation and flashing. Any manufacturer's warranty will be voided if installation and usage instructions are not followed. It is recommended that the cedar siding be installed per manufacturer's guidelines and recommendations by wood siding associations, such as the Western Red Cedar Lumber Association, including priming all surfaces including the back and ends before installing. Additionally, the use of furring strips will help promote drainage of any incidental water that may penetrate the cedar cladding.

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