Dear Sir: Is it OK to put antifreeze in a toilet bowl when winterizing a beach cottage that has a septic system or should it be all drained and sponge dried? Thank you. - Anonymous
Blackdog Design/Build/Remodel President Dave Bryan: Draining is not as desirable as antifreeze due to the likelihood of not being able to remove all the water in the case of a toilet. Allowing sewer gas back into the house is another problem with draining both toilets and sink traps.
Using antifreeze is a typical solution for winterizing toilets; however, it is important to use antifreeze designed for a boat or RV. These antifreeze products are environmentally friendly and should not cause harm to your septic. Make sure you drain the tank first and then introduce the antifreeze into the tank and flush it so that you get antifreeze in the parts of the toilet you can't see or reach.
Additionally, follow the instructions on the concentration level required. Since we are on the topic, all the sink drains should have antifreeze poured down the drain, as well, so the water in the trap does not freeze. Lastly, just shutting off your water is not enough. Any standing water in the pipes needs to be drained off after the water is shut down.
Open up all faucets and valves to release any trapped water so it can all drain to the lowest point.
These simple steps should keep the plumbing in your cottage damage free for the winter.
Send your home improvement questions for Dave Bryan to Ask the Expert, The Eagle-Tribune, 100 Turnpike St., North Andover, MA 01845 or firstname.lastname@example.org.