{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"pavers"},"result":{"entity_type":"calculator","id":"pavers","calculator_id":"pavers","canonical_url":"https://tttkmbb.com/construction/pavers","name":"Paver Calculator","title":"Paver Calculator – Pavers, Bedding Sand, Gravel Base and Joint Sand from Area and Paver Size","category":"construction","category_name":"Construction & Home","tool_name":"estimate_pavers","featured_mcp_tool":false,"description":"Counts the pavers for a patio, path or driveway from the area (or length × width), the paver size and the joint gap, adds waste, and estimates the bedding sand, the crushed-stone base (volume and tonnes at 1.6 t/m³) and the jointing sand from the joint geometry. Planning estimate only.","use_when":"You need to order concrete or clay pavers (or setts) plus the sand and aggregate under them for a known area.","do_not_use_when":"The surface is poured concrete (use concrete-slab), tiles bedded in adhesive with grout (use tile), or you only need the aggregate weight for a layer (use gravel).","inputs":[{"name":"area_unit","label":"Area unit","type":"enum","required":false,"default":"m2","values":[{"value":"m2","label":"Square metres (m²)","aliases":["m²","sqm","square metres","square meters","metric"]},{"value":"ft2","label":"Square feet (ft²)","aliases":["ft²","sqft","square feet","imperial"]}],"description":"Unit of the area input; areas are reported in both m² and ft².","example":"m2"},{"name":"area","label":"Area to pave","type":"number","unit":"m² or ft²","required":false,"max":100000,"exclusive_min":0,"description":"Area to pave in m² or ft² (see area_unit); alternatively give length and width.","example":20},{"name":"length","label":"Length","type":"number","unit":"m or ft","required":false,"max":1000,"exclusive_min":0,"description":"Length of a rectangular area (m when area_unit is m2, ft when ft2); used with width when area is not given."},{"name":"width","label":"Width","type":"number","unit":"m or ft","required":false,"max":1000,"exclusive_min":0,"description":"Width of the rectangular area (m or ft)."},{"name":"paver_length_mm","label":"Paver length","type":"number","unit":"mm","required":false,"default":200,"max":2000,"exclusive_min":0,"description":"Paver length in millimetres (200 × 100 mm is the common rectangular paver; 8 × 4 in = 203 × 102 mm).","example":200},{"name":"paver_width_mm","label":"Paver width","type":"number","unit":"mm","required":false,"default":100,"max":2000,"exclusive_min":0,"description":"Paver width in millimetres.","example":100},{"name":"paver_thickness_mm","label":"Paver thickness","type":"number","unit":"mm","required":false,"default":60,"max":200,"exclusive_min":0,"description":"Paver thickness in millimetres, used only for the jointing-sand volume: 60 mm for patios and paths, 80 mm for driveways.","example":60},{"name":"joint_gap_mm","label":"Joint gap","type":"number","unit":"mm","required":false,"default":3,"min":0,"max":30,"description":"Sand joint width between pavers in millimetres (2–5 mm for interlocking concrete pavers).","example":3},{"name":"waste_percent","label":"Waste allowance","type":"number","unit":"%","required":false,"default":5,"min":0,"max":50,"description":"Extra material for cuts, breakage and offcuts, applied as a multiplier (1 + waste_percent/100). 5 % for stack or running bond; 10 % for herringbone, circles and areas with many cuts.","example":5},{"name":"bedding_sand_depth_mm","label":"Bedding sand depth","type":"number","unit":"mm","required":false,"default":25,"min":0,"max":100,"description":"Screeded bedding-sand layer under the pavers; 25 mm (1 in) is standard for interlocking concrete pavers.","example":25},{"name":"base_gravel_depth_mm","label":"Base gravel depth","type":"number","unit":"mm","required":false,"default":100,"min":0,"max":600,"description":"Compacted crushed-stone base thickness: 100–150 mm (4–6 in) for patios and paths, 200–300 mm (8–12 in) for driveways.","example":100}],"outputs":[{"name":"area_m2","label":"Area","type":"number","unit":"m²","decimals":2,"description":"Area to pave."},{"name":"area_ft2","label":"Area","type":"number","unit":"ft²","decimals":2,"description":"Area in square feet."},{"name":"pavers_per_m2","label":"Pavers per m²","type":"number","decimals":2,"description":"1 / ((paver_length + gap) × (paver_width + gap))."},{"name":"pavers_per_ft2","label":"Pavers per ft²","type":"number","decimals":2,"description":"Pavers per square foot."},{"name":"pavers_before_waste","label":"Pavers (no waste)","type":"integer","decimals":4,"description":"ceil(area × pavers_per_m²)."},{"name":"pavers_needed","label":"Pavers to order","type":"integer","decimals":4,"description":"ceil(area × pavers_per_m² × (1 + waste_percent/100))."},{"name":"bedding_sand_m3","label":"Bedding sand","type":"number","unit":"m³","decimals":3,"description":"area × bedding_sand_depth."},{"name":"bedding_sand_tonnes","label":"Bedding sand","type":"number","unit":"t","decimals":2,"description":"Bedding sand at 1.6 t/m³."},{"name":"base_gravel_m3","label":"Base gravel","type":"number","unit":"m³","decimals":3,"description":"area × base_gravel_depth (compacted volume)."},{"name":"base_gravel_yd3","label":"Base gravel","type":"number","unit":"yd³","decimals":3,"description":"Base volume in cubic yards."},{"name":"base_gravel_tonnes","label":"Base gravel","type":"number","unit":"t","decimals":2,"description":"Base gravel at 1.6 t/m³."},{"name":"joint_sand_kg","label":"Jointing sand","type":"number","unit":"kg","decimals":1,"description":"Geometric joint volume (area × joint fraction × paver_thickness) × 1,600 kg/m³ of dry sand."}],"input_schema":{"type":"object","properties":{"area_unit":{"description":"Unit of the area input; areas are reported in both m² and ft².","type":"string","enum":["m2","ft2"],"default":"m2","examples":["m2"]},"area":{"description":"Area to pave in m² or ft² (see area_unit); alternatively give length and width. Unit: m² or ft².","type":"number","maximum":100000,"exclusiveMinimum":0,"examples":[20],"x-unit":"m² or ft²"},"length":{"description":"Length of a rectangular area (m when area_unit is m2, ft when ft2); used with width when area is not given. Unit: m or ft.","type":"number","maximum":1000,"exclusiveMinimum":0,"x-unit":"m or ft"},"width":{"description":"Width of the rectangular area (m or ft). Unit: m or ft.","type":"number","maximum":1000,"exclusiveMinimum":0,"x-unit":"m or ft"},"paver_length_mm":{"description":"Paver length in millimetres (200 × 100 mm is the common rectangular paver; 8 × 4 in = 203 × 102 mm). Unit: mm.","type":"number","maximum":2000,"exclusiveMinimum":0,"default":200,"examples":[200],"x-unit":"mm"},"paver_width_mm":{"description":"Paver width in millimetres. Unit: mm.","type":"number","maximum":2000,"exclusiveMinimum":0,"default":100,"examples":[100],"x-unit":"mm"},"paver_thickness_mm":{"description":"Paver thickness in millimetres, used only for the jointing-sand volume: 60 mm for patios and paths, 80 mm for driveways. Unit: mm.","type":"number","maximum":200,"exclusiveMinimum":0,"default":60,"examples":[60],"x-unit":"mm"},"joint_gap_mm":{"description":"Sand joint width between pavers in millimetres (2–5 mm for interlocking concrete pavers). Unit: mm.","type":"number","minimum":0,"maximum":30,"default":3,"examples":[3],"x-unit":"mm"},"waste_percent":{"description":"Extra material for cuts, breakage and offcuts, applied as a multiplier (1 + waste_percent/100). 5 % for stack or running bond; 10 % for herringbone, circles and areas with many cuts. Unit: %.","type":"number","minimum":0,"maximum":50,"default":5,"examples":[5],"x-unit":"%"},"bedding_sand_depth_mm":{"description":"Screeded bedding-sand layer under the pavers; 25 mm (1 in) is standard for interlocking concrete pavers. Unit: mm.","type":"number","minimum":0,"maximum":100,"default":25,"examples":[25],"x-unit":"mm"},"base_gravel_depth_mm":{"description":"Compacted crushed-stone base thickness: 100–150 mm (4–6 in) for patios and paths, 200–300 mm (8–12 in) for driveways. Unit: mm.","type":"number","minimum":0,"maximum":600,"default":100,"examples":[100],"x-unit":"mm"}},"additionalProperties":false},"output_schema":{"type":"object","properties":{"area_m2":{"description":"Area to pave. Unit: m².","type":"number","x-unit":"m²"},"area_ft2":{"description":"Area in square feet. Unit: ft².","type":"number","x-unit":"ft²"},"pavers_per_m2":{"description":"1 / ((paver_length + gap) × (paver_width + gap)).","type":"number"},"pavers_per_ft2":{"description":"Pavers per square foot.","type":"number"},"pavers_before_waste":{"description":"ceil(area × pavers_per_m²).","type":"integer"},"pavers_needed":{"description":"ceil(area × pavers_per_m² × (1 + waste_percent/100)).","type":"integer"},"bedding_sand_m3":{"description":"area × bedding_sand_depth. Unit: m³.","type":"number","x-unit":"m³"},"bedding_sand_tonnes":{"description":"Bedding sand at 1.6 t/m³. Unit: t.","type":"number","x-unit":"t"},"base_gravel_m3":{"description":"area × base_gravel_depth (compacted volume). Unit: m³.","type":"number","x-unit":"m³"},"base_gravel_yd3":{"description":"Base volume in cubic yards. Unit: yd³.","type":"number","x-unit":"yd³"},"base_gravel_tonnes":{"description":"Base gravel at 1.6 t/m³. Unit: t.","type":"number","x-unit":"t"},"joint_sand_kg":{"description":"Geometric joint volume (area × joint fraction × paver_thickness) × 1,600 kg/m³ of dry sand. Unit: kg.","type":"number","x-unit":"kg"}}},"formula":"pavers_per_m² = 1 / ((L + g) × (W + g)) with L, W, g in metres; pavers = ceil(area × pavers_per_m² × (1 + waste/100)); bedding_sand = area × depth; base_gravel = area × depth; tonnes = m³ × 1.6; joint_sand_kg = area × (1 − L × W / ((L + g) × (W + g))) × paver_thickness × 1600.","method":"Interlocking concrete pavement practice (pavers on a 25 mm screeded sand bed over a compacted crushed-stone base, sand-filled joints of 2–5 mm); base and bedding volumes are as-placed, loose aggregate compacts by 10–20 %, and polymeric jointing sand coverage from the bag may differ from the geometric figure. Planning estimate only; check quantities against the supplier's coverage figures and local code before ordering.","sources":[{"name":"Wikipedia – Pavement (architecture)","url":"https://en.wikipedia.org/wiki/Pavement_(architecture)","type":"reference","retrieved_at":"2026-09-24"},{"name":"Wikipedia – Bulk density","url":"https://en.wikipedia.org/wiki/Bulk_density","type":"reference","retrieved_at":"2026-09-24"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"20 m², 200 × 100 × 60 mm pavers, 3 mm joints, 5 % waste, 25 mm bedding, 100 mm base","inputs":{"area_unit":"m2","area":20,"paver_length_mm":200,"paver_width_mm":100,"paver_thickness_mm":60,"joint_gap_mm":3,"waste_percent":5,"bedding_sand_depth_mm":25,"base_gravel_depth_mm":100},"expected":{"area_m2":20,"pavers_per_m2":47.83,"pavers_before_waste":957,"pavers_needed":1005,"bedding_sand_m3":0.5,"base_gravel_m3":2,"base_gravel_yd3":2.616,"base_gravel_tonnes":3.2,"joint_sand_kg":83.5},"url":"https://tttkmbb.com/api/v1/calculate/pavers?area_unit=m2&area=20&paver_length_mm=200&paver_width_mm=100&paver_thickness_mm=60&joint_gap_mm=3&waste_percent=5&bedding_sand_depth_mm=25&base_gravel_depth_mm=100"},{"name":"200 ft², 229 × 152 mm (9 × 6 in) pavers, 3 mm joints, 5 % waste, 150 mm base","inputs":{"area_unit":"ft2","area":200,"paver_length_mm":229,"paver_width_mm":152,"joint_gap_mm":3,"waste_percent":5,"bedding_sand_depth_mm":25,"base_gravel_depth_mm":150},"expected":{"area_m2":18.58,"pavers_per_m2":27.81,"pavers_per_ft2":2.58,"pavers_needed":543,"bedding_sand_m3":0.465,"base_gravel_m3":2.787,"base_gravel_yd3":3.645,"base_gravel_tonnes":4.46,"joint_sand_kg":57.1},"url":"https://tttkmbb.com/api/v1/calculate/pavers?area_unit=ft2&area=200&paver_length_mm=229&paver_width_mm=152&joint_gap_mm=3&waste_percent=5&bedding_sand_depth_mm=25&base_gravel_depth_mm=150"}],"faq":[{"q":"How many pavers per square metre?","a":"About 48 for 200 × 100 mm pavers with 3 mm joints (50 with no joint), 28 for 229 × 152 mm and 11 for 300 × 300 mm; the joint is added to both dimensions before dividing."},{"q":"How thick should the base be?","a":"100–150 mm (4–6 in) of compacted crushed stone for patios and walkways on well-drained soil; 200–300 mm (8–12 in) for driveways or clay soils, placed in compacted lifts of about 100 mm."},{"q":"Is edge restraint included?","a":"No. Add the perimeter length of edge restraint (plastic, concrete or steel) and the spikes; without it the pavers spread and the joints open."}],"tags":["paver calculator","how many pavers","pavers per square metre","paver base gravel","bedding sand","patio pavers"],"related":[{"calculator_id":"gravel","reason":"Weight and volume of other aggregate layers."},{"calculator_id":"tile","reason":"Rigid tiles with grout joints instead of sand-set pavers."},{"calculator_id":"concrete-slab","reason":"Poured concrete alternative for the same area."}],"links":{"html":"https://tttkmbb.com/construction/pavers","markdown":"https://tttkmbb.com/construction/pavers.md","json":"https://tttkmbb.com/construction/pavers.json","api":"https://tttkmbb.com/api/v1/calculate/pavers","schema":"https://tttkmbb.com/api/v1/calculators/pavers","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T03:45:08Z","next_actions":[{"tool":"run_calculator","calculator_id":"pavers","reason":"Run Paver Calculator with the inputs above."}],"links":{"markdown":"https://tttkmbb.com/construction/pavers.md"}}