Formulas for cleaning fireplace surfaces

The Old House Web

Problem: My chimney is cleaned and ready for winter, but the bricksin the firebox are stained and ugly. How can I clean them?

Solution: Here are some cleaning formulas from the University ofMichigan Extension Service. Always wear rubber gloves when using these cleanersto protect your hands.

Formula 1: Mix one ounce of soap and one ounce of tablesalt with enough water to make a cream. Rub mixture into brick surface withcloth; allow to dry at least ten minutes and remove with stiff brush.

Formula 2: Make a thick mixture of soap or detergent, pumice, a littleammonia and hot water. Paint the mixture on the surface and let dry. Rub offwith a wet scrub brush. You are using alkali and a mild abrasive to remove thegreasy soil.

Formula 3: Shave a bar of naptha soap into a container and add 3 quartsof water. Bring mixture to a full boil until the soap melts. Cool. Add 1 cupammonia and one pound of pumice. Mix thoroughly. Brush in onto all sootysurfaces and let stand one hour or more. Rub off with a stiff-bristle brush.Rinse "gook" away with warm water, then finish off with a mediumto strong detergent and rinse again with warm water.

Formula 4: Dissolve 8 tablespoons (1/2 cup) Trisodium Phosphate (TSP) orSpic & Span in one gallon of hot water. With stiff scrub brush, scrub bricksurface. Rinse with plenty of warm water. Repeat if soot or greasy stain is notremoved. More TSP may be added if necessary, up to 1 cup per gallon. This is avery strong solution; avoid getting on skin, carpet, or fabrics.


  • Some weathered old brick (50 years or older) may be soft and damaged by vigorous cleaning. Test a corner, and if this is so, just dust or sweep it.

  • If the fireplace is to be used for family entertainment such as popcorn popping, or marshmallow toasting, etc., it would be wise to have brick or stone fireplace front surface sealed so as to resist absorption of grease or oils, and smoky soot.

  • These formulas are intended for cleaning the firebox, fireplace face bricks and the hearth. For fire safety, your chimney should also be inspected and cleaned annually.

This article waswritten by Anne Field, Extension Specialist, Emeritus with references from MaryEllen Delsipee and Isabel Jones, previous Extension Specialists.

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