Question: The outside walls and trim of our house are covered with a black powdery mold that is really starting to look terrible!
The mold is especially noticeable on the eaves and trim that are painted white, but it is all over the siding boards, too.
My husband thinks we need to pressure wash the house and that will take care of the problem. What should we do?
Your Handyman: The dark, dirty coating you are seeing on the siding, fascia and eaves of your house is more than likely being caused by mildew, not mold.
Mold grows mostly in dark, enclosed areas that are not exposed to the sunlight while mildew appears frequently in the caulking and grout lines of tubs and showers, and on the exterior surfaces of homes located in coastal areas with high humidity like Santa Barbara.
Mildew is a fungus that thrives in moist environments and feeds on organic materials, including oils in alkyd-based paints and the cellulose thickeners often found in many latex-based coatings.
The most effective way to remove the mildew from your home’s exterior is to first kill it with a dilute solution of chlorine and then wash it off completely with either a garden house or a pressure washer.
Chlorine is most commonly known as the bleach used in your laundry room and is a powerful oxidizer that can damage plants, fabrics and cause severe burns to your skin or eyes. It must be handled in a safe and cautious manner.
First, wet down the exterior surfaces of your house that you plan to clean and any plants or shrubbery that are close to the house and may come in contact with the chlorine.
Use a Hudson-style pump garden sprayer to apply a diluted mix of 1 part chlorine to 7 or 8 parts water onto the siding and eaves while wearing old painting clothes and eye protection.
With the first spraying, you will almost immediately see the mildew start to fade and run down the siding, and it is best to let it sit for several minutes at least.
If the mildew is particularly heavy, it may require several applications of chlorine before all the mildew disappears. Then rinse it all off the house using a garden house or a pressure washer.
If you use a pressure washer, be careful not to damage the wood or stucco, or to blast off the paint, leaving bare wood that will have to be sealed.
A garden hose is probably the best choice for rinsing the house, unless you are prepping the house for a paint job, in which case the pressure washer is very effective at removing loose or flaking paint and any dirt, dust or cobwebs that may have accumulated.
If your home has excessive amounts of mildew, it likely has substantially eaten into and damaged the paint, and it’s probably time to have the house repainted after the mildew has been washed away.
If new paint is applied over the mildew, it will continue to grow under the new paint, so it is critical that the existing mildew is completely killed and washed away prior to painting.
Chemical mildew inhibitors called mildewcides can be purchased at most any paint store as an additive that is blended into the paint before it is applied to a house in a moist environment or to a house that has a history of mildew problems.
Mildewcide is an EPA-registered fungicide that can be safely used in paint coatings either inside or on the outside of your home, and it will not affect the color or reduce the performance of the paint.
In an area like Santa Barbara where, in a typical year, we experience the May Gray and June Gloom fog, it really is a good idea for any home to be painted with paint blended with mildewcide as a preventative measure.
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Question: My husband and I live in a northern Goleta tract home that was built in the 1960s, and we want to replace all the bedroom and closet doors.
The doors we have are just flat on both sides, and we have found a new door style that we like that has six panels on each side.
But we have no idea how to go about ordering the doors or arranging for them to be installed. Can you explain the process?
Your Handyman: Installing new doors is a relatively inexpensive way to give the home a new contemporary look, and the process is actually pretty simple.
A new door can be ordered either pre-hung or just loose. A door that is pre-hung will already be set with new hinges that are attached to a new door jamb, and the door will be pre-bored for a new lockset.
The jamb (the “b” is silent) is the wooden frame that surrounds the door on the top and both sides, and a pre-hung exterior door will usually include a new threshold nailed to the base of the new jamb.
A door that is not pre-hung is simply just the door itself without any mortising for the hinges or boring for the lock set.
The door jamb is screwed to a wall stud on each side, with shims filling the gap. The gap between the jamb and the wall studs is concealed with the casement trim that frames the door, both on the sides and top, and also on both the inside and outside of the door.
If you purchase your doors pre-hung, the existing casement trim will need to be removed along with the existing jamb and door.
It is unlikely that the old casement trim will be able to be removed intact without splitting or breaking, so you will probably need to have new casement trim installed and painted along with the new pre-hung door.
If you purchase new doors that are not pre-hung, you will need to have a carpenter size and trim the new doors to fit the old jambs, mortis the doors for hinges that match the position of the hinges in the old jambs, and then bore a hole in the new door for the lock set.
Your first step in the process of installing new doors is to find a carpenter who is experienced in hanging doors, and he can help you to measure for placing the order for the new doors to make sure they are the correct sizes.
The same carpenter can pick up the doors for you when they arrive at the store or lumber yard, deliver them to your house in his truck, and install them correctly.
If you are considering purchasing both the doors and the installation from a big box hardware store, make sure that you personally meet the carpenter beforehand who actually will be doing the work and check his references.
My recommendation is that you purchase the doors pre-hung so the doors, jambs and casement trim are all brand new.
You will need to select a new casement trim and order it at the same time as the doors, also with the assistance of your carpenter.
Most doors and trim can be ordered with a coat of primer paint that is applied at the mill, and this will make your job a lot simpler if the doors, jambs and trim can have a color top coat of paint applied while sitting in your garage before the installation. Then just touch-up painting will be needed after the installation is complete.
