Author: DIYMeter Team

Quick answer: deck sealer or stain is bought by the gallon, and one gallon usually covers roughly 150 to 300 square feet per coat. Gallons needed = deck area × coats ÷ coverage per gallon. Always check the coverage printed on the can.

Example: a 12 ft by 12 ft deck, two coats

• Deck surface: 12 × 12 = 144 sq ft
• Two coats: 144 × 2 = 288 sq ft to cover
• Coverage assumed: 200 sq ft per gallon
• Gallons: 288 ÷ 200 = 1.44, so buy 2 gallons

Do not forget

• Railings, stairs and balusters add area. Measure them separately and add them.
• Rough or weathered wood soaks up more, so coverage can fall near the low end.
• Many products call for one coat only, so read the label.

Quick table for a 200 sq ft per gallon product

Building the deck first? See how many deck boards for a 12×12 deck.

Prepare the wood first

Stain and sealer only work well on clean, dry wood. Before you buy, plan for these steps:

1. Sweep the deck and clear out the gaps between boards.
2. Clean with a deck cleaner to remove dirt, mildew and gray, weathered fibers. Strip old finish if it is peeling.
3. Let the wood dry fully, often 24 to 48 hours after cleaning or rain.
4. Do a water test: sprinkle a little water on the boards. If it soaks in, the wood is ready. If it beads up, wait longer or clean again.
5. New pressure-treated lumber may need to dry out before finishing. Follow the product label for how long to wait.

Measuring stairs and railings

Railings, stairs and balusters can add a surprising amount of surface. Use these rough methods and add the results to your deck area:

• Stairs: tread width × tread depth × number of treads, plus the risers if you are staining them.
• Solid railings: length × height × 2 for both sides.
• Baluster railings: a common shortcut is to treat the railing as a solid panel, length × height, which roughly allows for all four sides of each baluster.

For example, 30 ft of railing at 3 ft high counts as about 90 sq ft. Two coats would add 180 sq ft of coverage, or about another gallon at 200 sq ft per gallon.

Transparent, semi-transparent or solid stain?

• Clear sealer or transparent stain: shows the most wood grain, but usually needs reapplying most often.
• Semi-transparent stain: adds color while letting grain show through. A popular middle ground.
• Solid stain: looks more like paint, hides wear and usually lasts longest, but hides the grain.

Coverage is different for each product, so always use the figure on the can for your final calculation.

When to apply

Choose a dry spell with mild temperatures. Many products recommend roughly 50°F to 90°F and no rain for at least a day after application. Avoid staining in strong direct sun, which can make the finish dry too fast and leave lap marks. Work a few boards at a time, along their full length.

Common questions

How many gallons of stain for a 12×12 deck?

About 1 to 2 gallons, depending on coverage and the number of coats. The example above needs 2 gallons for two coats.

Is one coat of deck stain enough?

Some products are designed for one coat, while others need two. Check the label, because an extra coat on a one-coat product can cause peeling.

How often should I re-stain my deck?

It depends on the product, climate and sun exposure. Transparent finishes may need attention every year or two, while solid stains often last longer.

Estimates only. Always follow the product label and local guidance.

Related: the DIY Project Budget & Materials Planner turns your measurements into quantities, costs and a shopping list.

Quick answer: Multiply your bed’s area in square feet by the mulch depth in inches, then divide by 324. The result is the number of cubic yards you need.

Cubic yards = square feet × depth (inches) ÷ 324

For example, a 200 sq ft bed at 3 inches deep needs 200 × 3 ÷ 324 = 1.85 cubic yards, or about 25 bags of 2 cu ft.

Why 324?

One cubic yard is 27 cubic feet. Spread 1 inch deep, it covers 27 × 12 = 324 square feet. So dividing by 324 converts square feet and inches into cubic yards.

Step-by-step

1. Measure your beds. For rectangles: length × width. For circles: 3.14 × radius × radius. For odd shapes, break them into rectangles and add them up.
2. Choose a depth. Most beds need 2–3 inches (see the chart below).
3. Calculate cubic yards with the formula above.
4. Convert to bags if buying bagged mulch: cubic yards × 27 ÷ bag size (cu ft).
5. Add 5–10% for settling and uneven ground.

Mulch coverage chart: 1 cubic yard

Bags of mulch needed (2 cu ft bags)

A 2 cu ft bag at 2 inches covers 12 sq ft; at 3 inches it covers 8 sq ft. A 3 cu ft bag covers 50% more.

How deep should mulch be?

• Flower beds and perennials: 2–3 inches.
• Vegetable gardens (straw or fine mulch): 2–3 inches.
• Around trees and shrubs: 2–4 inches, keeping mulch 3–6 inches away from trunks. Avoid “mulch volcanoes”, which trap moisture against bark.
• Paths and play areas: 3–4 inches for wood chips; playgrounds often need much deeper for fall protection.
• Topping up existing mulch: often just 1 inch is enough.

Too little mulch will not block weeds. More than about 4 inches can starve roots of oxygen.

Bulk vs bagged mulch

One cubic yard equals 13.5 bags of 2 cu ft. If bags cost $4, one yard bagged costs about $54, so bulk often wins above 2–3 yards once delivery is included.

Worked example

You have two beds:

• Front bed: 20 ft × 4 ft = 80 sq ft
• Circular tree ring: radius 3 ft = 3.14 × 3 × 3 ≈ 28 sq ft

Total = 108 sq ft at 3 inches: 108 × 3 ÷ 324 = 1 cubic yard. In 2 cu ft bags: 27 ÷ 2 = 13.5, so buy 14 bags (15 with a little extra).

Choosing a mulch type

• Shredded hardwood: stays in place on slopes, breaks down to improve soil.
• Pine bark nuggets: long-lasting, good for acid-loving plants, but can float in heavy rain.
• Cedar or cypress: pleasant scent and slow to decompose.
• Pine straw: light, cheap, popular in the US South.
• Dyed mulch: bold color but fades; choose products certified free of treated wood.
• Rubber or stone: long-lasting but does not feed the soil and can heat up in summer.

How to spread mulch the right way

1. Weed first. Pull weeds and remove debris so mulch does not trap them.
2. Edge the bed. A clean 2–3 inch edge keeps mulch in place and looks neat.
3. Water the soil. Mulch locks in moisture, so start with damp soil.
4. Optional barrier. Lay cardboard or newspaper for heavy weed areas. Avoid plastic sheeting, which blocks water and air.
5. Dump in small piles. Spread with a rake or by hand to an even depth.
6. Keep it off stems and trunks. Leave a small gap around plants.
7. Water lightly to settle the mulch in place.

Common mulching mistakes

• Piling mulch against tree trunks, which invites rot and pests.
• Adding new mulch on top every year without checking the depth, until it is 6+ inches thick.
• Using fresh wood chips mixed into soil, which can temporarily tie up nitrogen. Keep chips on the surface.
• Buying by the bag without doing the math, then making several extra store trips.

Frequently asked questions

How many bags of mulch are in a yard?

13.5 bags of 2 cu ft, or 9 bags of 3 cu ft.

How often should I replace mulch?

Top up organic mulch every year to maintain 2–3 inches. Fully replace it every 3–5 years or when it becomes matted.

When is the best time to mulch?

Mid to late spring, after the soil warms, and again in fall to protect roots over winter.

Bottom line

Use square feet × depth ÷ 324 for cubic yards, then convert to bags if needed. Aim for 2–3 inches in most beds and add a little extra for settling. Try DIYMeter’s free gravel and mulch calculator for an instant answer.

Prices are typical US ranges and vary by region and season.

Quick answer: A 12 × 12 room is 144 square feet. That equals 16 square yards or about 13.4 square meters.

Knowing the floor area is only the first step. Below, you will see how to use that number to estimate flooring, carpet, tile and paint for a 12 × 12 room, including the extra material you should buy for cuts and waste.

How to calculate square footage

Square feet = length (ft) × width (ft)

12 ft × 12 ft = 144 sq ft.

If your measurements include inches, convert them to feet first. For example, 12 ft 6 in = 12.5 ft. A 12 ft 6 in × 12 ft room = 12.5 × 12 = 150 sq ft.

Quick conversions for a 12×12 room

Is a 12×12 room big?

A 12 × 12 room is a comfortable average bedroom in the US. It fits a queen bed with nightstands and a dresser, or works well as a home office, nursery or guest room. Most building codes require a bedroom to be at least 70 sq ft, so 144 sq ft is roughly double the minimum.

Flooring for a 12×12 room

Always add a waste factor for cuts, mistakes and future repairs:

Flooring is sold by the box. If one box covers 22 sq ft, you need 159 ÷ 22 = 7.2, so buy 8 boxes.

Carpet for a 12×12 room

Carpet usually comes in 12-ft-wide rolls, which makes a 12 × 12 room easy: one piece 12 ft long, or 16 sq yd with no seams. Many installers still add about 10% for trimming, so plan on 17–18 sq yd.

Tile for a 12×12 room

• 12 × 12 in tiles: each covers 1 sq ft. 144 tiles + 10% = 159 tiles.
• 12 × 24 in tiles: each covers 2 sq ft. 72 tiles + 10% = 80 tiles.
• 18 × 18 in tiles: each covers 2.25 sq ft. 64 tiles + 10% = 71 tiles.

Paint for a 12×12 room

1. Wall area: 48 ft perimeter × 8 ft = 384 sq ft.
2. Subtract one door (≈ 20 sq ft) and one window (≈ 15 sq ft) = 349 sq ft.
3. At 350–400 sq ft per gallon, you need about 1 gallon per coat.
4. Two coats = about 2 gallons. The ceiling (144 sq ft) needs roughly 1 more gallon for two coats.

See our guide on how much it costs to paint a room for a full budget.

Baseboard and trim

Baseboard follows the perimeter: 48 ft, minus door openings (about 3 ft each). One door = 45 ft. Add 10% for corner cuts, so buy about 50 linear feet.

Measuring irregular rooms

Not every room is a perfect square. For an L-shaped room, split it into rectangles, calculate each one, then add them together. For example, a 12 × 12 area plus a 4 × 6 closet nook = 144 + 24 = 168 sq ft.

Tips for accurate measurements

• Measure wall to wall at floor level, not along baseboards.
• Measure twice, in two places, because walls are rarely perfectly straight.
• Round up to the next half foot when buying materials.
• Keep one extra box of flooring or tile for future repairs; dye lots can change.

Budget example: renovating a 12×12 bedroom

Here is a rough US materials budget using the quantities above:

Professional installation would add labor on top, often $2–$5 per sq ft for flooring alone. Doing the painting yourself and hiring out only the flooring is a common way to save.

Common mistakes

• Forgetting the closet or doorway threshold when ordering flooring.
• Skipping the waste factor and running one box short mid-project.
• Using floor area instead of wall area to estimate paint.
• Not letting flooring acclimate in the room for 24–48 hours before installation.

Frequently asked questions

How many square feet is a 10×12 room?

120 sq ft. A 12×14 room is 168 sq ft, and a 12×15 room is 180 sq ft.

How many 12×12 rooms make 1,000 square feet?

About 7 (1,000 ÷ 144 ≈ 6.9).

Does square footage include closets?

For flooring, yes, include any closet you will cover. For home listings, rules vary by area.

Bottom line

A 12 × 12 room is 144 sq ft. Add 10–15% for flooring and tile, about 16 sq yd for carpet, and roughly 2 gallons of paint for the walls. Use DIYMeter’s free calculators to get exact amounts for your project.

Quick answer: Hiring a professional to paint an average room in the US costs about $1,100, with most projects falling between $200 and $2,000. Painting it yourself usually costs $100–$300 in paint and supplies.

Your exact price depends on room size, ceiling height, paint quality, prep work and whether you include ceilings and trim. Here is how to estimate it.

Cost to paint a room by size (professional)

Painters typically charge $2–$6 per square foot of floor area for walls, including labor and paint.

Add roughly $1–$6 per sq ft for ceilings and $1–$3 per linear foot for trim and baseboards.

DIY cost to paint a room

For a typical 12 × 12 bedroom with 8-foot ceilings:

Once you own the tools, your next room costs mostly just paint.

How to estimate how much paint you need

1. Measure the perimeter: add the lengths of all walls. A 12 × 12 room = 48 ft.
2. Multiply by ceiling height: 48 × 8 = 384 sq ft of wall.
3. Subtract openings: about 20 sq ft per door and 15 sq ft per window. One door and one window: 384 − 35 = 349 sq ft.
4. Divide by coverage: one gallon covers about 350–400 sq ft. 349 ÷ 350 ≈ 1 gallon per coat.
5. Multiply by coats: two coats = about 2 gallons.

Use the free paint calculator on DIYMeter to do this instantly for any room.

What affects the price?

Paint quality

Paint ranges from about $20 to $70 per gallon for most brands, with designer lines over $100. Better paint usually covers in fewer coats, which can offset the price.

Finish

Flat and matte hide flaws and suit ceilings and bedrooms. Eggshell and satin are easier to clean for living areas. Semi-gloss suits bathrooms, kitchens and trim.

Color change

Going from dark to light, or covering bright colors, often needs primer and an extra coat.

Prep work

Repairing cracks, filling nail holes, removing wallpaper or treating stains adds time and cost. Wallpaper removal alone can add hundreds of dollars.

Ceiling height and access

Vaulted ceilings, stairwells and rooms needing ladders or scaffolding cost more.

Location

Labor rates are higher in large metro areas. Painters typically charge $20–$50 per hour.

DIY vs hiring a pro

Money-saving tips

• Do the prep yourself (moving furniture, patching, taping) and ask the painter for a reduced quote.
• Paint several rooms at once; many painters discount larger jobs.
• Choose paint-and-primer products when covering similar colors.
• Buy paint in 5-gallon buckets for large projects; it is often cheaper per gallon.
• Get at least three written quotes and confirm what is included (ceilings, trim, number of coats).

Step-by-step: painting a room yourself

1. Clear and protect. Move furniture to the center, cover it, and lay drop cloths along the walls.
2. Clean and repair. Wipe walls with a damp sponge, fill nail holes with spackle, and lightly sand once dry.
3. Tape. Apply painter’s tape along trim, ceilings and outlets. Remove outlet and switch covers.
4. Prime if needed. Use primer over patches, stains, bare drywall or big color changes.
5. Cut in. Use an angled brush to paint a 2–3 inch band along corners, ceiling lines and trim.
6. Roll. Work in 3 × 3 ft sections in a “W” pattern, keeping a wet edge to avoid lap marks.
7. Second coat. Wait for the time on the can (often 2–4 hours), then repeat.
8. Finish. Pull tape while the last coat is slightly wet for crisp lines, then replace covers.

Hidden costs to plan for

• Moving heavy furniture, which some painters charge extra for.
• Drywall repair for cracks or water damage.
• Lead-safe practices in homes built before 1978, which require certified contractors for disturbing old paint.
• Painting doors and window frames, often priced per item ($50–$150 each).

Frequently asked questions

How long does it take to paint a room?

A pro can usually paint a standard bedroom in 4–8 hours. DIYers should plan a full day, plus drying time between coats.

Do I need two coats of paint?

Usually yes, for even color and durability, especially when changing colors.

Is it cheaper to paint walls and ceiling the same color?

It can save time on cutting in, but ceilings normally use flat ceiling paint, so you will still buy separate products.

Bottom line

Expect around $1,100 for a pro on an average room, or about $125–$225 to do a 12 × 12 room yourself. Measure first, calculate your gallons, and compare quotes so you know a fair price before you start.

Prices are US national estimates for 2026 and vary by location and project.

Quick answer: a paver patio needs two layers of material under the stones: a compacted gravel base (usually 4 to 6 inches) and a 1 inch bedding layer of sand. Volume = area × depth in feet, divided by 27 for cubic yards.

To count the pavers themselves, see how many pavers for a 10×10 patio. For more on base stone, see how much gravel you need.

Example: a 10 ft by 10 ft patio

Area: 10 × 10 = 100 sq ft. Gravel: 100 × 0.333 = 33.3 cubic feet, and 33.3 ÷ 27 = 1.23 cubic yards. Sand: 100 × 0.083 = 8.3 cubic feet, and 8.3 ÷ 27 = 0.31 cubic yards.

Add an allowance

Compaction and uneven ground use extra material. Add about 10% to 15%: gravel 1.23 × 1.1 = 1.36 cubic yards, sand 0.31 × 1.1 = 0.34 cubic yards.

Tips

• Compact the base in layers of no more than about 2 inches at a time.
• Screed the sand level and do not compact it before laying the pavers.
• Depths vary with soil and use, so check your paver maker’s guidance, and use thicker bases for driveways.

Related: the DIY Project Budget & Materials Planner turns your measurements into quantities, costs and a shopping list.

Flooring is sold in boxes, not square feet, and the box count is where most people get caught out. Measure the room, add an allowance for cuts and mistakes, then round up to whole boxes.

Step 1: measure the room

For a rectangular room, multiply length by width. A 14 ft x 18 ft room is 252 square feet. In metric, a room 4.2 m x 5.5 m is 23.1 square metres.

For an L-shaped or irregular room, split it into rectangles, work out each area and add them together. Subtract areas that will not be floored, such as a built-in cupboard, but not a small island or a doorway.

Step 2: add a waste allowance

You will cut boards to fit walls and around corners, and some pieces will be damaged or unusable. Typical allowances are:

• 5 to 10 percent for a straightforward straight lay in a simple room
• 10 to 15 percent for diagonal layouts, herringbone or rooms with many corners

Using 10 percent: 252 x 1.10 = 277.2 square feet. In metric: 23.1 x 1.10 = 25.4 square metres.

Step 3: divide by the coverage per box

The coverage is printed on the box. Divide your area, including waste, by that figure and always round up.

• Imperial example: 277.2 / 22.5 square feet per box = 12.3, so buy 13 boxes
• Metric example: 25.4 / 2.2 square metres per pack = 11.5, so buy 12 packs

Step 4: price it

Multiply the number of boxes by the price per box. In the imperial example, 13 boxes at 45 dollars is 585 dollars before underlay, trim and fitting. Remember to include underlay, skirting or baseboard, transition strips and adhesive or fixings if your floor needs them.

Tips that save money and trouble

• Buy from the same batch. Colour can vary slightly between production runs, so buy all boxes together.
• Keep a spare box. If a board is damaged years later, a matching one is hard to find.
• Let it acclimatise. Many floors need to sit in the room for a day or more before fitting. Check the manufacturer’s instructions.
• Measure twice. Walls are rarely perfectly square, so measure the longest length and widest width.

Use the calculator

Our free flooring calculator does these steps for you in feet or metres and gives you a shopping list. To keep the whole renovation in one place, the DIY Project Budget and Materials Planner adds a budget tracker and project timeline.

These are planning estimates. Check box coverage and installation requirements with your supplier and the manufacturer before you buy.

Ordering too little concrete means a cold joint halfway through the pour. Ordering too much costs money and leaves you with a pile to dispose of. The good news is that the maths is simple: length times width times thickness, converted to the unit your supplier sells.

The basic formula

Volume = length x width x thickness. Measure everything in the same unit before you multiply.

In feet and inches (cubic yards)

Concrete in the US is sold by the cubic yard. One cubic yard is 27 cubic feet. Convert the thickness from inches to feet by dividing by 12, multiply, then divide by 27.

Example: a 10 ft x 10 ft patio slab, 4 inches thick.

• Thickness in feet: 4 / 12 = 0.333 ft
• Volume: 10 x 10 x 0.333 = 33.3 cubic feet
• In cubic yards: 33.3 / 27 = 1.23 cubic yards

In metres (cubic metres)

Elsewhere concrete is sold by the cubic metre. Convert millimetres to metres by dividing by 1,000.

Example: a 3 m x 3 m slab, 100 mm thick.

• Volume: 3 x 3 x 0.1 = 0.9 cubic metres

Add a waste allowance

Ground is rarely perfectly level, forms can bow and some concrete is lost when you pour. Adding about 10 percent is a common allowance. For the imperial example, 1.23 x 1.10 = 1.36 cubic yards. For the metric example, 0.9 x 1.10 = 0.99, so you would order 1 cubic metre. Ready-mix suppliers often have a minimum load, so ask about it.

If you are mixing bagged concrete

Check the yield printed on the bag. As a typical guide, an 80 lb bag yields about 0.6 cubic feet and a 60 lb bag about 0.45 cubic feet. For the 33.3 cubic feet slab above:

• 80 lb bags: 33.3 / 0.6 = about 56 bags, or about 61 with a 10 percent allowance
• 60 lb bags: 33.3 / 0.45 = about 74 bags

That is a lot of bags to mix by hand, which is why larger slabs usually use ready-mix delivered by truck.

How thick should a slab be?

A typical residential patio or walkway slab is about 4 inches (100 mm). Driveways and areas carrying vehicles are usually thicker, often 5 to 6 inches or more, and sometimes reinforced. Requirements depend on your soil, climate and local building rules, so check with your local authority before you pour.

Do not forget the base

Most slabs sit on a compacted gravel sub-base, commonly about 4 inches. Calculate the gravel the same way, length x width x depth, and order it separately.

Safety

Wet concrete is caustic. Wear gloves, eye protection and waterproof boots, and rinse skin that gets splashed.

Skip the maths

Our free concrete calculator works out the volume, bags and cost in feet or metres. If you are planning several jobs at once, the DIY Project Budget and Materials Planner combines materials, budget and a shopping list in one Excel file.

These are planning estimates. Confirm quantities with your supplier and follow local building rules and safety guidance.