TryBuildCalc

Putting Green Turf Calculator (Short-Pile Turf, Sand Infill & a True Base)

Size turf, sand infill and a screeded base for a practice putting green.

Inputs

Lawn Areas

Measurement Units

Applies to every dimension on this form — lawn sizes in feet, and pile height, base depth and fastener spacing in inches. Switching converts the figures already entered rather than reinterpreting them.

ℹ️Sets a sensible starting point for the pile height, the infill type and rate, and the base depth — all of which you can then change. On a hard surface it also switches the whole installation to a bonded one, because there is nothing to nail into.

A very short, texturised pile rolled hard and true. Putting-green guidance commonly cites 1.5-2.5 lb/sq ft of a rounded, kiln-dried sand, brushed and rolled in several passes to set the green's speed.

Area List

Add a row per rectangle. An L-shaped or curved lawn is best entered as the two or three rectangles it breaks into, measured to the widest point of each — that is how the turf gets cut anyway.

Area 1

ft
ft

Turf & Strip Layout

ℹ️The most important figure on this form. Turf is cut to length off a roll of fixed width, so the width decides how many strips your lawn needs and how much you pay for turf you cannot use. Check the actual roll width with your supplier before ordering.

ℹ️Most suppliers cut to length, so you pay for the linear metres or feet you need. Some sell full rolls only, in which case the order rounds up to whole rolls and the leftover is yours.

ℹ️Synthetic grass blades lean one way down the roll, so every strip in one continuous area must run the same way or the joint reads as a change of shade. That makes the running direction a single decision for the whole area — and it can change how much turf you buy by tens of percent.

Works out both directions for every area and uses the cheaper one, then tells you what the other would have cost. On an area whose width sits just over a roll width this is frequently a 15-30% difference in turf bought.

in

ℹ️The blade length. It sets how much infill is needed to hold the blades up, and it adds to the build-up depth you have to excavate for so the finished lawn sits flush with its edging.

in

ℹ️Spare length left at each end of every strip so it can be trimmed square to the edge. Added to both ends of each strip. Enter 0 to cut every strip exactly to length with nothing in hand.

%

ℹ️Extra on top of the strip layout, for trimming to curves, cutting around a tree or a manhole, and the piece that gets cut wrong. This is separate from the roll-width waste, which the layout already works out exactly — around 5% suits a simple rectangular lawn, 10% one with obstacles and curves.

Plan Narrow End Pieces Together?

When several areas each end in a narrow strip, those narrow pieces can be cut side by side out of one length of roll instead of one length each — they all still run with the pile, so it is a legitimate cut rather than a rotated offcut. Leave this off to keep each area on its own strips, which is simpler on site and harder to get wrong; turn it on to get the shared cut list and a smaller order.

Ground Preparation

Compacted Aggregate Base?

Finer material that screeds to a very smooth, true surface — commonly used as the top course over a coarser base, and on its own for putting greens where flatness matters most.

in

ℹ️The depth AFTER compaction — the finished thickness under the turf. Published guidance puts a residential turf base at 3-4 in (75-100 mm), deeper for pets, heavy rain or vehicle loads.

%

ℹ️How much of its loose volume the aggregate loses under the compactor, typically 15-20%. The order is worked out by DIVIDING by what is left, not multiplying by the loss — at 20% you need 25% more loose material, not 20%.

Fine Levelling Course on Top?
in

ℹ️A thin fine layer screeded over the coarse base, because a graded sub-base cannot be levelled to the flatness a turf surface wants. Usually 0.5-1.5 in (12-40 mm). Its depth counts toward the excavation as well.

Weed Barrier / Geotextile?

The usual position for a weed membrane: it blocks light so nothing germinates in the base, and it sits where you can still pin it down through the turf's fasteners.

in

ℹ️Membrane strips have to overlap rather than butt, or weeds find the joint. The overlap comes off each strip's effective width, so a 6 ft roll lapped 6 in covers 5.5 ft — which is why dividing the lawn area by the roll area comes up short.

Shock Pad Under the Turf?

Infill

ℹ️Infill weighs the turf down, holds the blades upright, shields the backing from UV and carries heat away. It is also the heaviest thing in the order by a wide margin, so it is bought by weight.

The default, and the cheapest by a distance. Rounded, kiln-dried grades flow between the blades instead of bridging; a sharp or unwashed sand packs and holds water. Published rates run about 1-2 lb/sq ft for a short residential pile and 2-3 lb/sq ft for a 1-2 in pile. Typical rate: 1-3 lb/sq ft.

ℹ️How much infill goes down per unit of lawn. Always check the turf manufacturer's own figure for your pile height — infill should sit in the bottom of the pile supporting the blades, not bury them. The result flags a rate that would do either.

Seams & Fixing

ℹ️The seam quantities come straight out of the strip layout, because a seam is exactly where two strips meet. If every area fits inside one roll width there are no seams at all and none of this is needed.

The standard, strongest method: 12 in wide tape run under the joint, adhesive troweled or gunned onto it, the two turf edges dropped on and weighted. Nothing penetrates the turf face, so the seam stays invisible.

5 in to 6 in galvanised or bright common nails (40D-60D) driven through the turf backing into the compacted base. The standard method wherever there is a base to nail into.

in

ℹ️The edge is where turf lifts, so this is the spacing that matters. Published guidance puts it at every 3-6 in (75-150 mm), tightening toward 3 in on an exposed edge. Counted fence-post style: one at each end of every run as well as those between.

ℹ️Most residential lawns are fastened only at the perimeter and seams, because the infill weight is what holds the middle down. A grid through the field is used on pet runs, play areas and anywhere the turf gets pulled at.

ℹ️Seam adhesive is quoted by the LINEAR foot of 12 in tape, not by area. A 5 gallon bucket covers roughly 250 linear ft, a 1 gallon pail about 50, and a 29 oz cartridge about 13.

Perimeter Edging?

Bends to a curve, which is what makes it the usual choice for a shaped lawn. Staked at roughly 3 ft centres.

Cost Estimation

Enable Cost Estimation?

Artificial Grass to Order

21.4 ft

6.5 m off a 15 ft (4.57 m) wide roll

Turf Area Bought

320.2 sq ft

29.8 m² / 35.6 sq yd, to cover 240 sq ft of lawn

20 ft x 12 ft lawn — 1 strip, 0 seams

Every area fits within a single roll width, so there are no seams at all.

Strips run along the length: 1 strip of 20.33 ft off a 15 ft wide roll.

The last strip only needs 12 ft of its 15 ft width, leaving a 3 ft x 20.33 ft offcut. You still buy the whole width, because the pile has to run the same way in every strip.

Where the Extra Turf Goes

Lawn actually covered240 sq ft22.3 m²
Roll width bought but not covered Pure geometry: you buy whole roll widths, and the last is usually partial. The one component a layout change can remove.+60 sq ft25% of the lawn
End trim at each strip end An allowance you set, not waste — spare length to cut square to the edge.+5 sq ft305 sq ft running total
Cutting and fitting allowance (5%) For curves, obstacles and the piece that gets cut wrong.+15.2 sq ft-
Turf bought320.2 sq ft33.4% over the lawn area

An area-based turf calculator reports only the last line as a flat 10% and misses the roll-width component entirely — which on this job alone is 60 sq ft.

Strip direction changes the order

Running the strips the other way round would have needed 65 sq ft more turf (6 m²). The cheaper direction was chosen for each area — set it out that way on site.

Ground Preparation

Excavate to: 5.85 in (14.9 cm) — 4 in of base plus 1 in of levelling course plus 0.6 in of turf and backing, so the finished lawn sits flush with its edging

Spoil to remove: 4.3 cu yd in the ground, bulking up to roughly 5.2-5.6 cu yd once dug

Decomposed granite / crusher fines, compacted volume: 3 cu yd (80 cu ft / 2.3 m³)

Order loose (+20% compaction): 3.7 cu yd = 5 US tons / 4.5 tonnes

Decomposed granite / crusher fines levelling course: 0.9 cu yd loose (1.3 US tons / 1.1 tonnes)

The loose volume is the compacted volume DIVIDED by (1 - 20%), not multiplied by (1 + 20%). Multiplying gives 3.6 cu yd, which is short — a mistake that leaves you a fraction of a load light at the very end of the job. Aggregate density is taken as 1.35 US tons per cubic yard loose; confirm it with your own supplier, since it varies with grading and moisture.

Infill

Kiln-dried silica sand (rounded) at 2 lb/sq ft (9.76 kg/m²): 480 lb / 218 kg (0.2 US tons)

That is 10 x 50 lb bag, about 4.8 cu ft of material, sitting roughly 0.24 in deep — 40% of the 0.6 in pile

Spread over the 240 sq ft of lawn, not the 320.2 sq ft of roll bought — offcuts never get infilled. Volume is estimated from a typical loose density of 100 lb/cu ft for this material; the purchase figure is always the weight.

Seams, Fixings & Accessories

Galvanised turf nails / spikes: 193 (1 pack of 250) 193 around the perimeter at 4 in centres

Weed barrier: 1 roll of 6 ft x 300 ft — 48 ft of strip, over the base, directly under the turf

A 6 ft roll lapped 6 in covers only 5.5 ft per strip, which is why dividing the lawn area by the roll area comes up short — that method would have given 1 roll.

Bender board (flexible plastic or composite): 4 x 20 ft for 64 ft of perimeter, plus about 23 stakes

Strip direction is doing real work here: running the strips the other way round would have needed 65 sq ft more turf (6 m²). The direction chosen per area is shown in the layout table — set it out that way on site, and keep every strip in one continuous area running the same way so the pile leans together.
Every area in this job fits within a single roll width, so there are no seams at all and no seam tape or adhesive is needed. That is the ideal outcome — a seamless lawn has nothing to come apart or show as a line.
The base alone is 5 US tons (4.54 tonnes) of aggregate, and 4.33 cu yd of soil has to come out first — which bulks up to roughly 5.2-5.63 cu yd once dug, so size the skip or the spoil heap on the bulked figure, not the hole.

Bill of Materials

Main material: 21.3 linear ft + recommended tools

+

Computed quantities come from your own areas, roll width and material settings above; the consumables below are general recommendations, filtered to this installation — actual needs vary by product, ground conditions and site access.

For Your Job

Artificial grass

21.3 linear ft

15 ft wide, 6.5 m

Find suppliers

Base aggregate — Decomposed granite / crusher fines

3.7 cu yd

5 US tons / 4.54 tonnes

Find suppliers

Levelling course — Decomposed granite / crusher fines

0.93 cu yd

1.25 US tons / 1.13 tonnes

Find suppliers

Weed barrier / geotextile

1 roll

6 ft x 300 ft, 48 ft of strip

Find suppliers

Infill — Kiln-dried silica sand (rounded)

10 bags

480 lb / 218 kg at 50 lb per bag

Find suppliers

Galvanised turf nails / spikes

1 pack

193 total at 250 per pack

Find suppliers

Perimeter edging — Bender board (flexible plastic or composite)

4 x 20 ft

64 ft of perimeter, about 23 stakes

Find suppliers

General Tools & Consumables

Utility knife and plenty of spare blades

Chalk line or marking paint

Tape measure (long, 100 ft / 30 m)

Stiff broom, or a power broom for anything sizeable

Wheelbarrow

Gloves and knee pads

Groundwork & Base

Plate compactor (hire)

Spade, shovel and landscaping rake

Screed bar or straight timber, plus a level

Skip, grab lorry or spoil removal

site-dependent

Drainage aggregate, channel or French drain

site-dependent

Fixing Down

Claw hammer or rubber mallet

Carpet kicker or turf stretcher

Infill

Drop spreader

Strip layout20 ft12 ftroll 15 ft1 strip, 0 seams — hatched area is 60 sq ft bought, not coveredBuild-up sectionTurf + infill0.6 inLevelling course1 inCompacted base4 inSubgradebarrierExcavate 5.85 in so the turf finishes flush

Plan drawn to the proportions of the dimensions entered, divided into the actual strips the layout needs; arrows show the pile direction every strip has to share, dashes mark the seams, and hatching marks roll width bought beyond the lawn edge. End trim at each strip end is included in the order but not drawn. Section layers are proportional to their real depths, with a minimum thickness so thin layers stay legible.

Looking for the verification checklist, reference tables, tips, or common mistakes?See the complete Artificial Grass / Synthetic Turf Calculator.

On a putting green, the base is the product

A practice green is the one artificial turf installation where flatness is the whole point rather than a finishing touch. The turf itself is a very short texturised pile, typically around half an inch, and it hides nothing — every stone, dip and soft spot in the base beneath telegraphs into the roll of the ball. That is why a green is built on a fine, screeded and rolled surface, usually decomposed granite or crusher fines over a compacted crushed base, worked to a far tighter tolerance than a lawn would ever need.

The infill does a second job here beyond holding the blades up: brushed and rolled in over several passes, it is what sets the green's speed. Published guidance commonly cites 1.5-2.5 lb/sq ft of a fine rounded kiln-dried sand, added in stages with rolling between rather than all at once. This calculator sizes the turf as real strips off the roll — worth planning so a seam does not cross a putting line — along with the base, the levelling course and the infill.

Artificial Grass Formula & Method

Every figure is computed in feet, square feet, cubic feet and pounds, and converted only for display. Feet is the natural working unit because the governing quantity — roll width — is a fixed manufactured dimension, and because the layout is an integer count of those widths across a measured area.

Step 1 — Strip layout, per area

For strips running along dimension A, across dimension B:

 

strips = ROUNDUP( B / roll width )

strip length = A + 2 x end trim

roll length = strips x strip length

turf area = roll length x roll width

lawn area = A x B

 

seams = strips - 1

seam length = seams x A

 

width waste = (strips x roll width - B) x A

The ROUNDUP is the whole point. You buy whole roll widths, so a 16 ft wide lawn off a 15 ft roll takes two strips and you pay for the other 14 ft of the second strip. That is not a waste allowance, it is geometry — and it is reported separately from the cutting allowance for exactly that reason. Note that the seam runs the length of the AREA, not of the over-long strip.

Step 2 — Which way the strips run

Option 1: strips along the length

A = length, B = width

 

Option 2: strips along the width

A = width, B = length

 

Choose the option with the smaller turf area;

if equal, the one with less seam.

 

CONSTRAINT: every strip in one continuous area

must run the SAME way (pile direction).

Synthetic grass blades lean one way down the roll, so a strip laid at ninety degrees to its neighbour reads as a different shade of green from most angles — the same effect as nap on a carpet. That constraint is what makes the running direction a single decision for the whole area, and it is why the usual offcut-rotating tricks from tiling and flooring are unavailable here. On a lawn whose width sits just past a roll width, swapping the direction frequently changes the turf bought by 15-30%.

Step 3 — The whole job, and the allowances

roll length = sum over areas of

(strips x strip length x count)

 

order length = roll length x (1 + cutting% / 100)

order area = order length x roll width

 

whole rolls = ROUNDUP( order length / roll length )

 

Over-purchase, split into its three causes:

width waste — geometry, removable by layout

end trim — an allowance you set

cutting % — curves, obstacles, mistakes

Splitting the over-purchase matters because only the first component can be designed out. A single blended waste percentage hides the fact that a lawn a foot over a roll width is paying for a whole extra strip, which a small change to the layout would delete entirely. The cutting allowance is genuinely separate: around 5% for a simple rectangle, nearer 10% with curves and obstacles.

Step 4 — Base aggregate and excavation

compacted volume = lawn area x compacted depth

 

loose volume = compacted volume

-------------------------

(1 - compaction% / 100)

 

weight = loose volume x loose density

 

excavation depth = base depth

+ levelling course depth

+ pile height + backing

 

spoil (bulked) = in-situ volume x 1.20 to 1.30

The division is the part published turf calculators get backwards. At 20% compaction the loose volume needed is 25% more than the compacted volume, not 20% more — multiplying leaves the order about 4% short, which is enough to stop the job at the final lift. Excavation is the full build-up, not just the base: getting that wrong is the commonest reason a finished artificial lawn stands proud of its own edging. Dug soil bulks up, so size the skip on the bulked figure, not the hole.

Step 5 — Weed barrier, in overlapping strips

effective width = roll width - overlap

 

strips = ROUNDUP( area width / effective width )

length = strips x area length x layers

rolls = ROUNDUP( length / roll length )

 

layers = 2 for a separation layer below the base

AND a weed membrane above it

A membrane is also a fixed-width roll laid in strips, with one difference: the strips must overlap rather than butt, or weeds find the joint. So a 6 ft roll lapped 6 in contributes only 5.5 ft per strip, and dividing the lawn area by the roll's nominal area comes up short. Unlike turf, a membrane has no pile direction, so its strips are always run whichever way needs fewer of them.

Step 6 — Infill, seams and fixings

infill weight = LAWN area x rate (lb/sq ft)

infill bags = ROUNDUP( weight / bag weight )

infill depth = (weight / density) / lawn area

 

tape rolls = ROUNDUP( seam length / roll length )

adhesive = ROUNDUP( seam length / linear ft per pack )

or, glued down:

= ROUNDUP( area / sq ft per pack

+ perimeter / linear ft per pack )

 

perimeter fasteners = ROUNDUP( perimeter / spacing ) + 1

per area

field fasteners = ROUNDUP( area / spacing² )

edging pieces = ROUNDUP( perimeter / piece length )

Infill goes on the lawn area, never the roll area — offcuts are never infilled, and on a job with heavy layout waste the difference is a whole pallet. Adhesive is the one line with two different bases: a seam bead is quoted per linear foot of 12 in tape, a full glue-down per square foot of surface, and using one for the other is out by an order of magnitude. Perimeter fasteners are counted fence-post style, one at each end of a run as well as those between, applied per area because each lawn is its own closed loop.

Worked Example

This example walks through your current inputs above, using the same steps as the Formula section.

Input Values Used

InputValue
Green20 ft x 12 ft (6.1 m x 3.66 m)
ApplicationPutting green
Roll Width15 ft (4.57 m)
Strip DirectionWhichever wastes less (recommended)
Pile Height0.6 in (1.5 cm)
Allowances2 in end trim per strip end, plus 5% for cutting
BaseDecomposed granite / crusher fines, 4 in compacted, 20% compaction
InfillKiln-dried silica sand (rounded) at 2 lb/sq ft (9.76 kg/m²)
Seam MethodSeam tape + turf adhesive

Step 1 & 2 — Strip Layout, Both Directions

AreaCalculationResult
GreenROUNDUP(12 / 15) = 1 strips of 20 + 2 x 0.17 = 20.33 ftThe other way round: 2 strips, 370 sq ft of turf305 sq ft of roll, strips along the length last strip uses 12 ft of its 15 ft width
Whole job1 strips across 1 area20.3 ft of roll = 305 sq ft

Step 3 — Turf to Order, and Where the Extra Goes

CalculationResult
Lawn actually covered240 sq ft (22.3 m²)
(1 strips x 15 ft of width) less the lawn width, over the run+60 sq ft roll-width waste (25%)
1 strips x 2 x 2 in of end trim x 15 ft+5 sq ft end trim
20.3 ft x (1 + 5% cutting allowance)21.4 ft of roll
Order21.4 linear ft (6.5 m) = 320.2 sq ft bought, 33.4% over the lawn

Step 4 — Base Aggregate and Excavation

CalculationResult
240 sq ft x 4 in / 1280 cu ft compacted (3 cu yd)
80 / (1 - 20%)3.7 cu yd loose to order multiplying instead of dividing would have given 3.6 cu yd — short
100 cu ft x 100 lb/cu ft5 US tons (4.5 tonnes)
240 sq ft x 1 in / 12, then / (1 - 20%)0.9 cu yd of decomposed granite / crusher fines (1.3 US tons)
4 in base + 1 in levelling + 0.6 in pile + 0.25 in backingexcavate 5.85 in (14.9 cm)
Spoil, bulked 20-30% once dug5.2-5.6 cu yd to cart away

Step 5 & 6 — Infill, Seams and Fixings

CalculationResult
240 sq ft x 2 lb/sq ft480 lb (218 kg / 0.2 US tons) of kiln-dried silica sand (rounded)
ROUNDUP(480 / 50)10 x 50 lb bag
(480 lb / 100 lb/cu ft) / 240 sq ft0.24 in deep — 40% of the 0.6 in pile
0 seams x their strip runs0 ft of seam (0 m)
ROUNDUP(64 ft / 0.33 ft) + 1 per area193 galvanised turf nails / spikes — 1 pack of 250
Strips at (6 - 0.5) = 5.5 ft effective width, then ROUNDUP(48 / 300)1 roll of barrier (48 ft of strip)
ROUNDUP(64 / 20)4 x 20 ft of bender board (flexible plastic or composite), about 23 stakes

Figures above are rounded for display; the real quantities are always calculated from full, unrounded values.

Therefore, covering 240 sq ft of lawn (22.3 m²) takes 21.4 linear ft of 15 ft wide turf — 320.2 sq ft bought, 33.4% over the lawn area — laid as 1 strip with 0 seams, over 5 US tons of base, with 10 bags of infill.

Disclaimer: This calculator provides approximate results for planning and estimation purposes only. Actual requirements may vary based on site conditions, materials, workmanship, and local building regulations. Always consult a qualified engineer, architect, or construction professional before making final decisions.

FAQ

Commonly 1.5-2.5 lb/sq ft of a fine rounded kiln-dried silica, applied in two or three passes with brushing and rolling between rather than in one go. The rate is doing two jobs: supporting a very short pile, and setting the speed of the green. More sand, well rolled, gives a faster truer surface up to a point; too much buries the pile and kills it. Add it in stages and test the roll as you go, rather than committing the whole quantity first.
A compacted crushed aggregate base of around 4 in, finished with a fine screeded and rolled course of decomposed granite or crusher fines — and worked to a much tighter tolerance than a lawn. A half-inch pile hides nothing, so any dip, stone or soft spot in the base shows up directly in the roll of the ball. Spend the time on the screed: it is the single thing that separates a green that putts true from an expensive green carpet.