How to Lay Mortar in a Yard

Examine the local building regulations to ensure that your new yard project will not affect any buried utility lines or rights of way in the neighbourhood.

Clear away all surface stones and debris. Decide how deep the layer of mortar will be depending on whether tile, brick, natural stone or a concrete slab will cover it. For most domestic uses, a 1-inch thickness of mortar above 1 1/2 inches of compacted fine sand and 4 inches of gravel is adequate. Sum these thicknesses together with the thickness of the stone or tile cover above the mortar and dig a trench to that depth.

Create a slight slope for drainage away from the house and toward a drain or drainage ditch. It should slope approximately one-half inch for every 4 feet of horizontal distance and check the slope with the level. Backfill any holes. Use the hand tamper to flatten the sloping surface. Allow the surface to rest for two days.

Line the sides of the trench with the hardboard planks that will act as forms for the mortar. Keep the planks in place by hammering the wooden stakes into the ground every 2 feet. Fill the surface with gravel or crushed rock to the depth required. Rake the gravel to form an even distribution. Compact the gravel with the hand tamper.

Pour the sand into the surface and rake over until even. Use the hand tamper to compact the sand. Do not disturb the sand bedding any further. Cover with a thick tarpaulin overnight to protect from rain, animals and birds.

Prepare the tiles, stone or other surface cover that the mortar will bind. Mortar sets quickly so the top cover must be laid as soon as possible after pouring. Combine at least one part Portland cement and four parts sand with water for the mortar. In areas where winters are severe, increase the proportion of cement in the mix up to one part cement to 1 1/2 parts sand. Add just enough water for the mortar to feel plastic and workable.

Pour the mortar over the compacted sand in the yard and even out gently with the rake and trowel until it is the required thickness. The mortar is ready for laying the top surface. Remove the border planks and support stakes after the top surface has been laid and grouted.