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Volume 5 Issue 5“Building Confidence”May 2007



We hope your renovation, new construction or small project is going as well as you expected. This newsletter is about questions from people who need a bit of knowledge and direction to ensure that their project does complete well. For those new to our website, welcome. Maybe a question answered here could make the difference in your project, as well.

What's New

Last month I wrote about a mission trip to Northern Mexico that my wife, myself and members of our church were involved with. Thank you for the nice emails I received concerning that project. It is nice to know that there are people in our world that have compassion for those who are not as fortunate as themselves.

I added a new dog house plan since we got back and an article on installing aluminum and vinyl soffits.

We are on the go again for three weeks. We were invited to go to Portugal with my daughter, her Portuguese born husband, their two kids and his parents. We will be visiting their extended family and seeing some of the country. We are leaving Saturday and will be back around the 18th of July. As usual, when traveling, I take my laptop to stay in touch with you, our members and your questions. Please bare with us if I don't get back to you within my usual day or two. I might be stuck on a beach in the Algarve with no Internet connection.

Ask Away!

Here are some of the questions I answered last month:

I'm installing a new floor on both concrete and wood base.
Cork flooring is suggested instead of lamination floor in order to
avoid some kind of sound when you step on it. Could you give some
advice. Thank you!


Hi Mel,

Actually, I've installed cork tile (12x12, glue down) on a concrete floor. It does seem to absorb sound of walking on it, a bit. It is not soft like a carpet, but softer than hardwood. You've probably seen samples. It also comes in a laminated floor system installed as a floating floor which is also good for concrete, which I have also installed. The main problem with a glue down tile is that the concrete floor has to be smooth and flat. We had a bit of work to prepare the concrete for the tile. That is add concrete floor level compound to the rough or low areas and knock off the high spots. The next step was to glue the tile down as you would a ceramic tile or wooden parquet tile.

Adhesive is used rather than mortar as for ceramic, of course.

Hope this helps,


I am designing a new two story residence on wood pilings in
Galveston Texas. What wall height for 9 foot ceilings (from top
of subfloor to top of double plate) works best with vertical
exterior plywood sheathing and interior gyp board. Pulling some
plans I note anything from 9 foot 1-1/8 inches to
9 foot 4-1/2 inches. what does a standard 9 foot stud measure.
How best to do this.

A 9' pre-cut stud measures 104 5/8". Adding the 4 1/2" for the 3 plates gives a ceiling height of 109 1/8". This gives clearance for the drywall on the ceiling and the flooring, giving the finished ceiling height at about 9'.

The vertical siding usually comes in lengths of 8', 9' or 10'. The overhang and the pitch of the roof determines the length (height) of the siding sheets since the siding fits up under the soffit material, as shown here. A tip with siding, to break up the long lines of a 2 storey installation, we install a belly band around the house, at the bottom, in the middle and/or at the gable end.


Hi Dave,I have been trying to find info on calculating florescent
lighting for general lighting in a given area with no such luck.
The area I need to light is the kitchen dining area.I am not going
to use recessed or task lighting.It is a old house and just want
to brighten up area with new lighting.One part is 5x7 and kitchen
dining area gets
wider and continues 10x10.I was thinking of a 2-40 watt fixtures
in the 5x7 area and 2-40 watt fixtures in the 10x10 area spaced
If you have any input,I would appreciate it.

Thanks Joe

Hi Joe,

I just searched the internet and found a site which has lighting layout software with calculator.It shows that a double tube 40 watt fluorescent fixture is good for the 5x7 area and another fixture of the same size is also good for the 10x10 area. You can even choose the 32 watt energy saving fixtures.

Hope this helps,


I've completed installing stringers on my new deck but I noticed
that the two outside stringers (2x12) are cupped and somewhat
twisted so when I try to install the bottom 4x4 posts there're
way out of plumb. Short of replacing the stringers what would
you recommend?

This is why it is important to look at the lumber we buy very carefully when we are buying it. It seems that all the good stuff is exported and we are left with the junk. Most building supply stores let you pick your own lumber.

To your problem - use the stringers as support, but you will have to shim between the post and the stringer with small wedges. As you put the shims in tighten the bolts and shim together to get the post plumb. You may need to get longer bolts to allow for the shims.

This is an opportunity to use my wedge jig: Jigs 4: Feather Wedge Jig


Thanks Dave, I made the jig for the shims. Works great! You ARE the man!

Hey good job, Bob,

Glad to know it worked for you!

Thanks for letting me know,


Hi Dave and thanks for your down to earth advice site.
My question is how much concrete can one or two people
reasonably pour using a rented mixer. I'm planning to pour
a circular slab on grade (with integrated footing) perhaps
18' or 20' diameter for a small round building
(more questions on that later).
Is this size slab too large to tackle?
Thanks, Adrian.

Hi Adrian,

This slab isn't too large for a pour by mixer and wheelbarrow, but is near the limit. I would suggest a person on the mixer, one on the wheelbarrow and one in the slab as a minimum. The guy in the slab needs help with screeding. Four or more people would be better. You are looking at about 6 cu. yards which is about 50 to 55 wheelbarrows at 3 cu. ft. each. Try to place the gravel/sand mix near the slab, the less wheeling the better. You also need more sand/gravel than 6 yards, get at least 8 yards allowing for waste and compaction when mixed. Try to get navvy jack, which is the correct mixture of sand and gravel for concrete. Have lots of water on hand, as well. This will be a long day counting the finishing, if all goes well.


I would like advice on a garage door height. We have a choice
because we are building. I would like to make the door opening
large enough so if I get a tall vehicle and add a ski rack on
top so I can go into the garage without having to take the ski
rack off before going into the garage.


Hi Vicki,

I assume you are talking about an overhead garage door. These are dependent on the ceiling height. Usually they want 12" from the top of the door to the under side of the ceiling, which is called headroom. You can get low headroom hardware for a minimum headroom of 6" at an extra cost. The standard sizes of the doors are, (width x height): 9x7; 9x8, etc. I've built garages up to a ceiling height of 16' so a logging truck can get inside a 14' door. Pick the size of door you need then ideally add 12 inches for headroom.

I have a 10' ceiling in my garage, since it is also my workshop. I put in a 9x8 door with glass top panel for light.

Check with your local dealer to see what sizes he has in stock and the rough opening required.


I will address this to the Wood Guru Superior. Need some help in
"WoodTurning". I have decided to try my hands at making some bowls.
I bought all the equipment and plan on taking some classes locally
so I can get some good training in to trying to teach myself.
My Question:
I want to get some square stock [2" X 2"] to practice on. What type
of wood would you recommend??? I don't want to go and buy some
expensive stuff just to turn into wood chips. Hope you can help.

Hi Kelly, good to hear from you again,

I inherited my Dad's old lathe and have been playing on it, as well. I found out that softwood doesn't have a smooth finish, not like hardwood. For practice I used anything I had in my shop. I used a piece of spruce with knots and all. Watch those knots. So if you have to buy something to practice on I would go with a piece of pine or fir rather than spruce. Take shallow passes to knock the corners off, until the 2x2 is rounded out. Then try different tools. It is actually not that hard and quite fun, I enjoyed playing around. I actually made stuff that was useful, my first time, but I should have made them out of hardwood. After awhile the pieces cracked up. The spruce, pine, fir we get in our dimension lumber is sold with a fair amount of water still in it, 19% they say. This is fine for practicing, but for a finished piece get a nice piece of dry hardwood. You will really see the difference in the finish you can get. Also make sure your tools are sharp all the time so they won't tear the wood instead of peel it nicely.

Classes seem like a good idea. I never took wood turning in school. Don't know why, maybe I was sick that day.

Hope this helps,


Hi Dave,
Got a question on how to clean the black fungus off of a 11 year old
shingle roof?
2nd- will this cleaner harm the roof, and is the weather too hot to
do it now?
I was planning on removing the old roof and replace it, got some cost
figures, and when a carpenter friend of mine came over to give me an
estimate on helping me, he thought I was nuts to replace it. He told
me I could get some chemical that can be sprayed on, to remove the
black fungus. Then, he said there was some sort of metal strip that
we could put across the ridge line on both side s of the roof ridge
that would keep the fungus at bay once it's cleaned off. Do you know
what he was talking about, as he said that he'd heard of this
installation, but had never done on, and couldn't remember what the
metal composition was........
Thanks Eric

Hi Brandy,

I did my own roof, an asphalt shingle roof, and used a pressure washer with a solution of 1 cup of bleach per gallon of water and some liquid detergent. It had a black algae on it with clumps of green/yellow moss. It came out great and hasn't reappeared for at least a year. This won't harm the roof, as long as you don't get too close to the roof with the pressure wand. The weather shouldn't be too hot to leave footprints on the shingles. The metal strip he is referring to is a zinc strip sold at hardware stores and building supply centers. This is effective to a certain degree when it rains the rain leaches the zinc down the roof to kill the moss. This metal strip is nailed along the ridge of the house. I think it is better to clean the moss and algae off the roof every few years rather than use the zinc strip.


redoing my kitchen and would like to know about painting over walls
that are knotted pine that's been painted with a varnish.
What do I need to do to paint over this.
thanks, Charles

Hi Charles,

Sand off the varnish to remove any gloss and prime with an oil based primer sealer that says it is compatible over varnish or urethane. The varnish you refer to, unless in a older house, is probably a polyurethane, such as "Varathane" or equivalent. Some of the new acrylic latex primers are compatible with the first coat being a urethane. The main point is to read the label on the chosen primer to be sure it is compatible with the urethane and to sand it lightly.

Hope this helps,


Hi Dave,

I'm building a "clubhouse" for our six year old in the back yard.
Thank you for the "how to build a door" article as that was one
of my concerns.
My question is this: I'm planning on using vinyl siding, but
would like to include a disguised 'adult door' for future use
when it becomes my shed later on. Does it make any sense to try
and cover that door with the vinyl siding? No doubt this is a
"dumb question", but I hope to keep the look for my daughter as
if it were all hers.

Thanks and have a great day,

Hi Brad,

Cutting out the door is a good idea. Vinyl siding is easy to remove and modify around the door at a later date. I don't think this is a dumb question at all. It shows you are planning ahead, which is always good.


Well, that's it for this month. Hope our website builds confidence for you. If you are not sure, ask, before making a wrong move. It may save you some cash, too.


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