To safely enjoy a roaring fire this winter, you should clean your fireplace from top to bottom. A deep clean is recommended at least once a year. A regular dusting out is a good thing, but a deep clean is for your own safety. Wait at least 48 hours since you last used your fireplace before starting this project.
Your chimney is an integral part of your fireplace, so before you clean the cavity of the fireplace you should have the chimney cleaned. For peace of mind, use a professional for this task.
Cover the Surrounding Area
Before you start working, put on a pair of old work clothes and don your safety glasses, gloves, and dust mask. Gather all the materials in the tools and materials list and start by double bagging a trash can with heavy-duty trash can liners. Spread drop cloths or newspapers on any nearby furniture and on the floor.
Clear the Hearth
Remove the grate and take it outside. Cleaning the grate and the ash screen is one of the last things you will do, unless your ash screen is connected right to the fireplace. In that case, brush down the screen with a stiff brush now, and then move on to the next step.
Remove the Ash
Shovel any ash into your lined trash can. Once the main part of the fireplace is shoveled out, place some newspaper in the bottom of the fireplace. Use a stiff brush to scrape the sides and back of the fireplace. Reach up as far as you can and let the scrapings fall onto the newspaper. After that is complete, remove the newspaper and toss the bundle into the trash can. If you have a shop vac, use it to remove the last remaining particles of dust.
Use a Cleaning Solution
For the next part, you will want to open your flue. Any fumes from the cleaning solution will get sucked up the chimney.
In a bucket filled with one gallon of hot water, add in 6 tablespoons of TSP* (tri sodium phosphate) and 1 cup of bleach. Put on your rubber gloves, dip your brush into the mixture and start scrubbing from top to bottom. Do not let this mixture dry on any surface. Do one section at a time and rinse with clean water as you go.
Brush the Screen
Clean the screen by using a stiff brush and finish by dusting with a clean dry paint brush. The brush will get all the tiny particles out of the screen. If you have a glass screen, now is a good time to clean it. If you can find hearth cleaner, it works very well on screens and fireplace glass.
Go outside to where you left the grate and use a stiff brush to clean it off. You can now reassemble your fireplace. Make sure everything is thoroughly dry before igniting another fire.
Assess the Surface for Possible Repairs
Now that everything is clean, it would be a good time to inspect your fire bricks and mortar. Replace any bricks that are cracked and if any of the mortar is disintegrating, you should replace that as well.
Inspect the Chimney Cap and Trim Trees
The outside of the fireplace is almost as important as the inside. If you did hire a reputable chimney sweep, they probably already did this step for you. If you are like me, I check it myself to make sure all is good. So get up on the roof and inspect the chimney cap. If the screen is damaged, replace it -- you won’t want little critters making a home in your chimney. While you are up there, check if there are any overhanging branches from nearby trees. Should a spark escape your chimney screen, it could ignite a nearby branch. Trim branches back as far as you can.
One last tip: If you toss a small handful of salt on a fire it will loosen any soot in the chimney. The salt turns the soot into smoke and away it goes, right out the chimney!
*Note: not all states allow the sale of TSP, but there are TSP substitutes usually found in the paint department of a home improvement store.