We receive many inquiries from our customers about plumbing trim kits. Many different plumbing manufacturers will make their items as two seperate pieces, one piece is the trim kit and another piece is the valve or rough in valve. Some manufacturers may even sell the handle seperate. The trim kit is the finished piece that is mounted on top of the sink (faucet) or on the wall (shower kit).
Here is an example of a faucet trim:
Here is an example of a tub shower trim:
The valve is the second part to a trim kit, the valve is the part that goes behind the wall or under the counter. The valve is what you hook the water lines to.
Here is a picture of a faucet valve:
Here is a picture of a shower valve:
Valves and trim kits can not be interchanged between manufactures. If you have a Moen valve installed in your shower then you must use a Moen trim kit. You can not use a Moen valve and a Grohe trim kit.
When purchasing a faucet or shower kit you also need to be aware that manufacturers offer more than one type of valve. For example a shower valve can be a pressure balance valve or a thermostat valve. A pressure balance valve means that the water pressure stays constant and you can only control the water tempurature, this is the most common valve. The more elite valve is the thermostat valve which you control both the water pressure and the water tempurature. Not all trim kits will fit a pressure balance valve or a thermostat valve so you need to make sure that you purchase the right trim for the right valve.
If you are looking at a faucet valve they usually come in three different styles. A center set, a 4" centers, and a wide spread or 8" center. A center set valve is a single hole faucet, these are the bathroom faucets which only have one handle.
Here is an example:
A 4" center faucet is the most common faucet. This means that there are three wholes in the sink or countertop where a faucet is suppose to go. If you were to measure from the center of the left hole to the center of the right hole you should have 4". These means you have a 4" center set faucet. There are many types of 4" center faucets, some are called mini-widespread faucets and some are on an escutcheon plate.
Here is an example of a 4" center faucet with escutcheon:
A widespread faucet or 8" center faucet also has three holes in the sink or counter top. The only difference is that the length from the center of the left hole to the center of the right hole is 8".
Here is an example of an 8" center faucet. Notice that the handles are spaced further apart:
Once again if you are purchasing a faucet as a trim kit make sure that you order the correct valve for the installation.
Tips:
1. Most manufacturers will have a "T" in the model number if it is a trim kit. If you are not sure and the item seems to be about 65.00-100.00 cheaper than anywhere else, most likely you are purchasing a trim kit. The best thing is to read the full description very carefully and then call or email the person who is selling the item.
2. Make sure that you know the model number that you are purchasing to ensure that you can match up the right valve or trim.
3. If you are building a new home you can always purchase just the valve and have your plumber rough in the valve first. Then when all of the finish work is done you can purchase the trims and install them over the valve. The trim is the last thing to install on your fixture. If you install them too early they might be damaged while other construction is occuring in your house. Most manufacturers have a lifetime warranty but not if the trim has been scratched or ruined during construction or with a strong cleaning agent.
4. If you already have a valved installed in your wall make sure you know the manufacturer and model number before you purchase a new trim. If you do not know the model number, try to find out the manufacturer and about how old the valve is. You can then call the manufacturer and they can tell you which trim kits will fit your valve.
I hope that you have found this information helpful.
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