Brick is a beautiful, durable building material. It's also quite expensive to replace, so you might presume you're stuck with the colour unless you paint it. But painting is not your only option. You can tone down brick colour with concrete stain or thinned paint. This job can be quite easy if you also stain the mortar, but with a little extra work, you can retain the mortar colour and stain only the face of the brick. Make it lighter and less vivid with a whitewashing technique, or tone it darker with a deeper colour stain.
Clean the brick. Interior brick in good condition might just need to be brushed or vacuumed free of surface dust. Scrub brick with detergent and water if it's very soiled, or use a power washer for large expanses of exterior brick.
Choose your stain. Home improvement stores and masonry showrooms will have concrete or masonry stain, which, like stain for wood, soaks into brick to change the colour while still letting the natural characteristics show.
Choose water-based paint and thin it with paint conditioner for a wider range of colour choices. Paint conditioner is a clear additive that, when added in sufficient quantities to paint, makes the paint translucent, like a stain. It's available at most paint and home supply stores.
Protect adjacent surfaces. Staining brick is a messy job. Use masking tape and masking paper or plastic to mask off walls and trim, and dust sheets to protect the floor or ground.
Mix the stain. Masonry stain will not require thinning. If you are mixing paint and paint conditioner, you'll have to experiment a bit to get the look you want. Start with a 50:50 mix, and apply it to some spare bricks or an unobtrusive area. Increase the paint ratio for an opaque look, or add more paint conditioner for a more translucent effect.
Apply the stain to both the brick and mortar. Use an airless sprayer for exterior brick staining, or a brush and roller with at least a 3/4-inch nap for smaller areas or interiors. Avoid putting on too heavy of a coat, because the stain will be quite runny and prone to dripping. Keep checking your work for drips and runs and brush or roll them out.
Use a 4-inch short nap roller or a brush to paint just the face of the brick, and leave the mortar the original colour. Work carefully, but don't worry about a little bit of stain overlapping onto the edges of the brick. Wipe excess with a damp rag.
Most masonry and brick stains are water-based and should not require any sealing to make them last longer. Use the right paint if you're mixing paint conditioner. Use 100 per cent acrylic latex paint for exteriors, and a good interior latex paint for interior brick. Test colours first to be sure you're getting the effect you want. If mixing a colour yourself, mix enough in a 5-gallon bucket (or buckets) for the entire job to ensure colour uniformity.