subject: Special Jobs In Plumbing - Clay Soil Plumbing Considerations [print this page] Basement construction in clay soil poses several problems. Expansive soil can cause cracking in the foundation, basement walls and floor if proper precautions aren't taken. Natural movement caused by expansive clay soils also require special precautions to be taken when installing basement plumbing. Pipes can burst if plumbing is too rigid.
Floating walls keep the walls and floors from being damaged as the home moves with the expansion of clay soil. This allows the walls to move independently from the floor of the basement. The pipes need to be able to move upward with the floor but not push against the first floor of your home. The drainage pipes under the basement floor need to be able to breathe as well.
When you install bogs, washing room, or a mudroom in the cellar you want to make allowance for natural movement of clay soil. Installing flexible growth couplings and enlargement joints on cellar plumbing will make allowances for this movement and keep the pipes from dribbling at the joints or cracking.
Your pipes should really be new during installation. If you're working with existing pipes confirm not to go from one sort of metal to another. If you happen to be using copper stay with copper pipes and the same applies for other metals. Take care to not to change the size of pipes incidentally. It's possible to go from one size to another but it's not necessarily sometimes smart idea. You need to also commence with new pipes whenever it's possible. Older pipes can have lead solder split up while you are working with them and you don't desire this to get into your water supply, regardless of if it is for a shower and not drinking water.
Anywhere you are attaching one length of pipe to another you want to add a growth coupling. Growth couplings are made from a synthetic polymer sleeve that slips over the ends of both pipes. Steel clamps are used to hold the coupling and pipes together. Once applied, the coupling will make allowance for a touch of movement in the pipes. It is vital to be sure you've got the growth couplings and not regular couplings as the growth couplings are made to respire with the home and the regular couplings aren't made to move.
When installing a shower you may use reverse floating walls to stabilise pipes in the cellar and permit movement in the apex of the pipes. You must put the maximum amount of the plumbing in the same area as practical and use the same wet wall. A chase should be included and access can be either along a wall or in the ceiling.
Flex lines are needed for water supply lines. The main water supply line should go into the chase and have flex lines attached in that area to the pipes used in the basement. The most logical place for the chase access panel is in the utility room along with the hot water heater.
Besides having enlargement joints and flexible couplings installed the pipes there should be adequate space between the pipes and the ceiling / floor to avoid having the pipes push into the ceiling as the ground expands with the changes in the moisture in clay soil.
Growth joints will be required for installation of ground water drainage pipes also. This is often done below the cellar floor, above the foundation. Drains can be placed in the cellar floor permitting moisture that does enter the cellar to run into the drainage system and away from the home.
