To avoid lap marks, roll the full height of the wall and keep a wet edge
Lap marks are those ugly stripes caused by uneven layers of paint buildup. They occur when you roll over paint that’s already partly dry. (In warm, dry conditions, latex paint can begin to stiffen in less than a minute!) The key to avoiding lap marks is to maintain a “wet edge,” so each stroke of your roller overlaps the previous stroke before the paint can begin to dry.
To maintain a wet edge, start near a corner and run the roller up and down the full height of the wall, moving over slightly with each stroke. Move backward where necessary to even out thick spots or runs. Don’t let the roller become nearly dry; reload it often so that it’s always at least half loaded. Keep the open side of the roller frame facing the area that’s already painted. That puts less pressure on the open side of the roller, so you’re less likely to leave paint ridges
· Mix several cans of paint in a large bucket for a consistent color throughout the room
Paint color may vary slightly from one can to the next. If you have to open a new can in the middle of a wall, the difference may be noticeable. Mixing the paints together eliminates the problem. It’s best to estimate the amount of paint you’ll need and mix it in a 5-gallon bucket (a process called “boxing”).
When coverage is difficult to estimate, add more rather than less. You can always pour the leftover back into cans. For large jobs, use the bucket and a roller screen rather than a roller tray. It’s much faster to load your roller with the screen than to use a roller pan. Simply dunk the roller into the paint bucket, then roll it along the screen until it stops dripping.
· Clean dirty surfaces so the paint can form a strong bond
f you paint over dirty, oily surfaces, the paint will easily chip or peel off. So before painting, clean grimy areas with a deglosser or heavy-duty cleaner intended for prepaint cleaning. They work well to clean painted, varnished or enameled surfaces to improve the adhesion of the new paint. They’re ideal for cleaning greasy or oily areas like kitchen and bathroom walls and removing hand marks around light switches and doorknobs.
Wipe on the cleaner in a circular motion using a lint-free cloth or abrasive pad. Start at the bottom and work up. After the surface is clean, fill in any nicks and holes, then sand them smooth before painting. The cleaners are available at paint stores and home centers. Be sure to wear rubber gloves and eye protection.
· Calculate approximate amount of paint Required(in Liters)