It’s easy to think of the climate in Morocco as dry and therefore overlook the need for moisture control in construction.
There are two main sources of water infiltration in buildings: from above (rain) and below (the ground).
Addressing moisture from above:
Tops of “parapet walls” (those low walls along the the roof perimeter) and window sills are normally finished with the same painted stucco that is used on the façade. However, this stucco and paint are only intended for vertical surfaces, not horizontal. Despite not being typically used in Morocco, copings on top of walls and window sills are necessary to keep moisture from penetrating exterior facades and damaging finishes. Without coping, water will slowly absorb into the stucco. Copings can be made of aluminum, precast concrete, stone, or ceramic. All of these materials inherently resist moisture and sun exposure that horizontal surfaces are subject to. In any case, the copings must be sloped to drain back towards the roof, away from the front façade.
Rooftop terraces, balconies, and terraces are normally finished with floor tile. However, it is important that the tile have a layer of waterproofing installed under it. This waterproofing can be roll-on sheet products, or liquid products applied with a brush. The waterproofing and tile must turn upwards at the perimeter so that any water accumulating on the floor does not soak into the walls.
Additionally, the entire surface of the terrace must slope down towards a floor drain that is appropriately sized and with a drain cover that keeps debris from clogging the pipe.
Addressing moisture from below:
Due to the challenges of waterproofing foundation walls, basements should typically be used only as storage and garage space. However, if basement areas are to be used as occupied rooms, then proper waterproofing and foundation drainage are critically important.
Basement walls should have exterior waterproofing the full height of the wall down to the footing. They should also have a layer of gravel fill the full height of the wall, and drainage pipe running along the base of the footing to prevent water from accumulating in the soil outside of the basement.
All exterior façade walls, whether or not there is a basement, should have waterproofing to keep moisture from soaking into the building. Some common methods are:
– Continue underground waterproofing up the wall at least 30cm
– A layer of horizontal waterproofing at the bottom of the wall.
– Use water repellant stucco and paint.
– Avoiding soil and planting against the wall (gravel is better)
– Perimeter drains.
– Don’t attach irrigation system pipes and shutoff valves to the wall, and aim sprinklers away from walls.
– Put tile behind and hose spigots.