Get Off the Ground

Many homes in the country are built slab-on-grade which means a concrete pad is poured and the home is built without a basement. This is because the water table may be too high for a basement or a basement would be too expensive to build, as in the case of being close to bedrock. However there are costs to pay for having this type of a structure:

1. Inaccessible Pipes, Electrical and HVAC

Putting in a pad means that all the wiring, heating, cooling, drains, water and other amenities have to be buried in the pad when it is poured. So if you want to add anything later it would be a very costly enterprise. This is esepcially true if the flooring is right on the pad.

Unless Murphy’s Law has been repealed there will be maintenance issues of some kind or another. Even if the repairman, plumber or electrician is able to fix the problem the floor in the area will have to be taken up before any work can be done. And this might included cutting or jackhammering the a hole in the pad. A crawlspace or shallow basement can allow access to every function and is cheaper to install than burying conduit and pipe in concrete.

2.  Insurance

Insurance companies don’t mind you not having a basement but want you to get the home off the ground. This is especially true in low-lying areas. Some even offer a break for every foot that the home goes up.

3.  Water and Pests

A raised floor also takes away the risk of rainwater getting to the slab and undermining it. In addition, a faulty gutter and downspout system can mean that water can get into the home or pool around the slab. This could cause rot in the sill plates. Insects, vermin and mold love damp areas and are attracted to rot.

4. Pilings

As the devasting Hurricane Ike in Texas has shown, pilings are solid. In areas where moisture in the ground is a problem getting up on pilings is a better idea than having a slab. Moiture moves through the ground and slabs can crack letting in water and even radon gas. Having the home up even a couple of feet off the ground and properly insulated can alleviate a lot of problems. As for access for wheelchairs a two foot rise accounts for a very shallow slope.

The main idea is to keep your floor above the ground so that you will have peace-of-mind.

Hardwood and Laminate Floor Underlayments

It used to be that only carpets needed cushioned underlays. This provided a comfortable base for any type of carpet but also smoothed over irregularities with the flooring.

Hardwood flooring underlayment used to mean a thick paper product that was placed down before the planks went on. This not only “quieted” the floor but prevented the subfloor from later rubbing against the undreside of the planks of some of the staples loosened.

Today there are many types of underlay, most of which came about with the advent of laminate flooring. These sheets not only quiet the floor but provide protection for hardwoods being placed on concrete floors. The most common types are the 3, 5, and 10mm foam which is also used for laminate. Most flooring contractors will put a vapor seal against the concrete before placing any type of a cushioning to prevent moisture from getting up into the flooring.

An eco-friendly underlayment features recycled rubber which can be obtained with both an adhesive and non-adhesive backing. This is made from old tires and can be used in both floors and ceilings. Cork is also a product that is used.

For your needs, it depends on where you are going to put it and how much you want to spend.

Floor Leveling

Before a new floor can be put down one of the biggest concerns is the level of the floor. In other words you want to achieve “flatness,” getting rid of the humps and filling up the hollows. because if you have humps and/or hollows the flooring may come away and begin to squeak or, if you have tile, crack.

1. Clean: Scrape any drywall, glue blotches or other obstacles off the floor. Sand if you have to. In this way you will know exactly what you are dealing with.

2. Check Level: To check on a floor nail two wood blocks of equal height at each wall or side of the room. Put in a nail in both and run a string from one block to the other fastening it tight. Make sure the string is level then measure down from the string to the floor at three (3) points: Side 1, side 2 and the middle of the room. The difference in the three measurements will tell you how much you have to either add or take away material. The differences should not be over 3/16″ over a 10 foot span.

3. Grind High Spots: Using a floor sand with 12 grit rock paper will get the floor down quicker but will raise a lot of dust so you will have to seal the room with plastic vapor seal. Recheck the floor between sandings.

4. Sunken Floor: If the floor is sunken then check the beam below it. There may be a structural problem. Often a depression in the floor can be cured by shimming up the floor, that is, by inserting wood between the beam and the sub flooring to raise it.

5. Low Spots: Flooring installers use a floor leveler, a compound that can be troweled on. This doe not take the place of large depressions in the floor. A long 2 X 4 is drawn across the wet leveler used to achieve level. This compound dries quickly (20 minutes) so you have to work quickly. make sure you clean you tools right away because leveler is hard to get off them.

Cement Board Sub -Floor

Most tile experts are meticulous about their sub-floors and that is why they choose cement board. It is used right on the bathroom floor and in the shower where strength is needed in a wet area.

Cement board is a matt of glass fiber rolled into a 4 X 8 foot sheet with wet cement. When it is dry it forms a solid, water-tight surface that can be used in wet areas like bathroom as and kitchens. Because of its composition it is incredibly strong and dent resistant, especially for bathroom walls where gypsum board might let ago with a hard knock. It is also water resistant and, if wet, will not promote the growth of mold.

Cement board has to be cut with a carbide-tip blade and be sure to use a dusk mask as the fine particles are like a dust storm. As for fastening, pre-drilling the holes is recommend and a ring-nail or screw can be used.

When attached a small space should be left between sheets and this to be filled with a joint compound or silicone caulking. Thinset can go right over top of the cement board and it will bond easily, probably more easily that with plywood or any other subfloor.

Cement board is heavy, but if it’s going on the floor this shouldn’t matter. Being twice the weight of gypsum board it is difficult to get up on the walls, especially above 8 feet.

It is expensive but them you will never have to worry about the integrity of your bathroom floor.

Subfloor for Tile

Tile is hard, long lasting and beautiful but all of these attributes can change in a very short time if there is a problem with the subfloor.

By its very nature tile is brittle. There is virtually no bending or twisting in a ceramic or porcelain tile. But it is attached to a huge under surface which may or may not be as static. Wood sub flooring, if not attached firmly, can move, shrink or be pushed up from forces below. if the tile is attached to this surface it will not be able to accommodate these movements and this is where cracks appear, at first in the grout and then in the tiles themselves.

In addition, tile that is placed directly on cement can be affected by the physical shortcomings of the concrete. If a cement pad cracks, then there is a good chance that the tile will crack or that there will be cracks in the grout. Tghis latter problem is a whole lot easier to fix.

New methods of placing down tile include mesh and mats which can move with the sub floor but keep the tile static. These subfloors are “waffle-shaped” and come in rolls which can be rolled out and attached to the floor. Then the mastic is applied and gets into the “dimples” in the plastic subfloor. When the tile is pressed down these hollows are filled with the adhesive and form pillars to support the tile.

Wood Subfloor Evaluation

Building a road over unknown ground has been tried before many times. Logging companies do it all the time to get out the timber. They just drive a bulldozer through an area that has been cut and that is the road. But it is not a permanent road. Because to make a permanent road there has to be a good base so the road will not shift. A floor is much the same. If it is not braced properly underneath, or if the decking material is not level, then you will get all sorts of problems.

If the new flooring is going into the main living area and there is wood underneath the surface will be prepared according to the material you choose to put down. Old linoleum floors are usually a good base for more linoleum or carpet if they are in good shape and secured well to the old surface. If there are small patches of linoleum missing sometimes a flooring contractor will use a leveling compound.
This makes more sense than to try and scrape it off as the old glue may be rock-hard in spots creating a huge mess.

Tile is different. It should never go onto the original wood subfloor as the moisture may cause problems like squeaking and warping down the road. A marante or thin plywood board covering should be fastened on top of the subfloor. Fasten it down placing wood screws in grids of 5″ separation.

As well it should never go directly down on linoleum or old tile. This old covering should be removed or the mastic may separate and the tile come loose. Covering the old linoleum surface with plywood would also suffice but tile would have to be removed before the new subfloor went down.