Basically, the roof is the place that is directly exposed to and affected by the environment, and is an important factor to pay attention to when constructing a house. However, according to Architect Pham Thanh Truyen (Director of Cat Moc Architecture - Construction - Training Company), for simplicity and economy, many houses do not have roofs that meet technical requirements, making it difficult to protect the house from harsh weather, especially in places where storms often occur.

Therefore, when constructing a roof, homeowners should pay attention to the following points.

Choose the right roof type

There are two common types of roofs: flat roofs (parallel to the ground) and sloping roofs (forming a certain angle with the horizontal). According to architects, it is necessary to consider the geographical context and purpose of use to determine the appropriate roof type.

For areas with high rainfall, midlands, mountainous areas... houses should use sloping roofs, common materials are corrugated iron, tiles or concrete, bitumen roofing. Sloping roofs help rainwater drain quickly, are waterproof, leak-proof and provide an airy, cool space with high heat dissipation function.

When designing a sloping roof, it is necessary to avoid placing the low roof position close to the neighbor's house, causing rainwater to overflow to other people's houses.

On the contrary, in plains, along the coast or places with a lot of wind and storms, homeowners can choose a flat roof. This type has the advantage of being durable and resistant to natural impacts such as storms because it has a relatively low slope, only fluctuating between 5-8%.

When constructing, flat roofs need to be solidly poured with concrete, and properly calculated to withstand sea winds and storms. For coastal projects, homeowners should not use metal trusses for roofing because they will quickly rust and deteriorate.

Double layer roof deck

According to the architect, with a flat roof, the roof floor should be made of 2 layers. The first layer is a concrete load-bearing floor, waterproofed, creating a slope to collect rainwater. The next layer can be made of perforated concrete panels, fired ceramics, Duraflex panels... The two floor layers are 10 cm apart, this gap helps with convection and ventilation.

With a two-layer design, the roof floor will be protected by the panels, not directly affected by the sun's heat, less elastic, and water-absorbent. Thanks to that, the top floor area will be cooler and more airy.

Choosing the right material

It is necessary to understand the physical and chemical properties of each type of material to apply it to the roof in the most reasonable way.

The most popular and economical material today is corrugated iron roofs, but they make a lot of noise when it rains and have poor insulation. Corrugated iron roofs also do not meet aesthetic requirements. Currently, there are many types of heat-insulating and sound-insulating corrugated iron on the market, but they only partially reduce the limitations.

Architects suggest that homeowners use tile or reinforced concrete roofs. Reinforced concrete roofs are popular in large cities thanks to their ability to utilize the roof area for gardening, storage, etc.

If tile roofs are installed with a system of steel and wooden trusses that are properly engineered, ensuring all structural layers, they will be durable and aesthetically pleasing. However, the cost of this material is quite high, homeowners should consider their financial ability and favorite architectural style when choosing.

Rainwater drainage system

The cross-section of the drainage pipe is calculated based on the average annual rainfall of the area, to prevent heavy rain. The slope of the roof floor must be at least 30% for tiled roofs, 10% for corrugated iron roofs, and 1% for flat roofs so that rainwater can drain completely, not stagnate, and overflow into the house.

Homeowners should install 2-3 trash balls in parallel (where water is collected and brought to the drain pipe), in case one water collection location is blocked.

Roof waterproofing

To avoid floor cracks and water seeping from the roof to the house, waterproofing must be done carefully. Architects suggest that homeowners use cement-based waterproofing, which is more durable and easier to apply.

During construction, homeowners apply layers of cement to the concrete surface, the cement mixed with the concrete layer will expand, sealing the pores of the concrete, limiting water seepage to the roof. If homeowners use asphalt for waterproofing, after a while this material will "age" and tear the waterproof membrane.

Bình Nghi