Topic
Walls
Wall measurements, substrate checks and practical preparation for renovation finishes.
Calculators
Aerated concrete block calculator
Calculates masonry volume and an estimated block count from wall dimensions, openings, block size, wall thickness and allowance.
Brick quantity calculator
Calculates wall area and an estimated brick count using the selected masonry thickness, mortar joints, openings and allowance.
Drywall sheet calculator
Estimates drywall sheets for repeated rectangular surfaces, subtracting openings and accounting for the number of layers.
Insulation calculator
Estimates insulation volume, board count and packs for walls, floors or ceilings, including multiple layers where needed.
Paint coverage calculator
Estimates the litres of paint needed from the stated coverage and number of coats.
Plaster mix calculator
Turns the area and average plaster thickness into an estimated material weight and number of bags.
Primer quantity calculator
Converts the product coverage into total litres and, when provided, the number of containers.
Wall filler calculator
Estimates the amount of wall filler for each layer, the total weight and the number of bags.
Wall area calculator
Calculates the area of all four walls and subtracts the area of door and window openings.
Wallpaper roll calculator
Estimates vertical strips and rolls from room dimensions, roll size, openings and pattern repeat.
Guides
Can You Paint or Wallpaper Fresh Plaster?
Fresh plaster should not be covered until it has reached the condition required by the plaster and finish manufacturers. A surface that feels dry may still hold moisture inside.
Gypsum Plaster or Cement Plaster: Which Fits the Job?
Gypsum and cement plaster are chosen for different conditions. The right option depends on moisture exposure, substrate, layer requirements and the next finish—not a universal ranking.
How to Tell if a Wall May Be Load-Bearing
A wall may look like a partition and still have a structural role. Plans and a qualified assessment matter more than a guess based on thickness, sound or location.
How Much Paint Do You Need?
Paint quantity comes from the area actually being coated, the coverage on the product label, the number of coats and a sensible allowance.
Why Does Paint Bubble or Blister?
Bubbles form when a paint film loses contact with its substrate or pressure builds below it. Moisture is one possibility, but the surface and earlier coatings also need checking.
How Long Does Paint Take to Dry?
Touch-dry, recoat-ready and fully cured are different stages. Use the product data sheet and the actual condition of the coating instead of one universal number of hours.
How Many Coats of Paint Do You Need?
The right number of coats depends on paint opacity, the contrast and absorption of the substrate, the application method and the finish you want.
Why Paint Peels Off Walls
Peeling paint means the bond to the substrate or an earlier coating has failed. Remove the weak layer and correct the cause before applying new paint.
Why Do Paint Streaks and Roller Marks Appear?
Visible lines after painting may be roller marks, lap marks, uneven sheen or uneven coverage. The appearance helps narrow the cause, but does not prove it on its own.
How to Calculate Average Plaster Thickness
Average coat thickness is a planning value taken from several measurements across the wall. The deepest local spot remains a separate check against the plaster system limits.
What Are Plaster Guides Used For?
Plaster guides provide a physical reference for a consistent wall plane when deviations are significant. They are a method of control, not a universal requirement for every surface.
Why Does Plaster Crack?
A crack may belong only to the plaster layer, or it may reflect movement in the substrate. Check its pattern, growth and surroundings before choosing a repair.
How Long Does Plaster Take to Dry?
Wait for the actual plaster system to reach the condition required by the next finish. Mix, thickness, substrate and room conditions all affect drying, so one fixed timetable is unreliable.
How Thick Can a Plaster Coat Be?
There is no universal maximum plaster thickness. Use the range in the selected product data sheet and treat average thickness, local depth and the number of coats as separate decisions.
Why Does Plaster Come Loose?
Loose plaster is an adhesion and substrate problem, not just a surface blemish. Remove failed material safely, find the cause and only then choose a compatible repair.
How Long Does Primer Take to Dry?
Continue when the primer is dry and compatible with the next material, not just when the surface feels less wet. The manufacturer’s instructions take priority over a universal time.
How to Choose the Right Primer
The right primer depends on the substrate and the next material, not just the word “universal” on the label. It can control absorption or help adhesion, but it cannot repair a weak wall.
Why Does Wall Filler Crack?
Filler cracking can be caused by shrinkage, a thick application, poor preparation or movement below the finish. Establish where the crack runs before repairing it.
How Long Does Wall Filler Take to Dry?
Surface dry, ready for sanding and ready for the next finish are different stages. Filler type, thickness, substrate and room conditions determine when to continue.
How Much Wall Filler Do You Need for a Room?
Wall filler quantity depends on the prepared area, average coat thickness, number of coats and the rate printed on the product. Calculate base and finishing compounds separately when needed.
Why Does Wall Filler Peel or Come Loose?
Peeling filler means that the bond to the substrate or earlier layer has failed. Remove unstable material, identify the cause and prepare a sound base before applying more filler.
How to Sand Wall Filler for a Smooth Finish
Sanding should refine a ready filler layer, remove ridges and blend small imperfections. It cannot replace levelling compound, correct deep hollows or repair a weak base.
Base Filler vs Finishing Filler: What Is the Difference?
Base filler addresses modest surface irregularities within its product limits, while finishing filler refines the surface for paint or thin wallpaper. The substrate and permitted thickness decide the sequence.
Can You Tile Over Plaster?
Tile can be installed over plaster when the layer is sound, cured, dry, clean and compatible with the adhesive system. Plaster alone is not proof that the substrate is ready.
How to Prepare a Surface for Tiling
A reliable tile installation starts with a sound, clean, sufficiently flat and cured substrate. Primer does not replace removing weak layers or fixing moisture.
How to Calculate Wall Area With Doors and Windows
Measure each wall section, add the areas and subtract only openings that will remain unfinished. Niches, reveals and projections need their own measurements.
When Is a Wall Crack a Cause for Concern?
A fine crack in paint or filler may be cosmetic, but growth, displacement, recurring lines, moisture or distorted openings call for assessment before cosmetic repair.
How to Check If a Wall Is Flat
Wall flatness is checked with a long straightedge in several directions, while a level or plumb line checks vertical alignment. Record where the high and low spots are.
Why Is My Wall Damp?
Dampness is a sign that water is entering or accumulating somewhere. Condensation, leaks, plumbing, adjacent rooms and the substrate can look similar from the surface.
How to Prepare Walls for Paint, Wallpaper or Tile
The finish changes the preparation standard. Paint needs an especially uniform surface, wallpaper can hide some minor texture, and tile needs a strong plane with compatible adhesion.
Why Do Bubbles Appear Under Wallpaper?
Small local bubbles may shrink while adhesive dries, but persistent or widespread bubbles point to air, moisture, adhesive or substrate problems that need diagnosis.
Why Does Wallpaper Fall Off the Wall?
Loose wallpaper is usually an adhesion or substrate problem. Inspect the boundary, moisture and wall preparation before attempting a local repair or replacement.
How to Choose Wallpaper Adhesive
Wallpaper adhesive selection depends on the wallpaper, its backing and weight, the wall and the application method. A universal label does not remove the need to check compatibility.
Why Do Wallpaper Seams Open?
Wallpaper seams open when neighbouring strips change size or lose contact with the prepared wall. Adhesive, absorption, edge pressure and drying conditions all deserve a check.
Can You Wallpaper Fresh Plaster or Filler?
Fresh walls are ready for wallpaper only when plaster or filler has dried, stabilised and been prepared for the chosen adhesive. A calendar date alone cannot prove readiness.
What Is Wallpaper Pattern Repeat and Why Does It Matter?
Pattern repeat is the recurring design that must line up across wallpaper strips. A larger or offset repeat increases cutting waste and can change the required roll count.
How Much Extra Wallpaper Should You Buy?
Wallpaper allowance depends on roll and wall dimensions, pattern repeat, cuts and room shape. Check the strip layout instead of applying one universal percentage.