Major Types of Construction

Major Types of Construction. When we live in a city, we witness buildings and landscapes changing around us. We observe modern designs, more skyscraper projects, marvelous architectural visions, and much more. We notice them and then pass by. But have you ever thought about how they are constructed? A normal person won’t think much about it, but a contractor or a student of architecture will surely want to know “what type of construction is this?”

We can categorize construction into various parameters. These include, but are not limited, to the material used, owners, or types of structure. However, here we will discuss construction based on fire resistance. Typically there are 5 types of construction based on the fire resistance level of a building. It ranges from Type 1, the most fire-resistant, to Type 5, the least. Let’s take a look:

Type I Construction: Fire Resistant

As the name suggests, these buildings are built to bear high temperatures for a long duration without collapsing. Therefore, the materials used for these buildings are also non-combustible. The International Building Code (IBC) Table 601 mentions these materials.

The roofs, walls, columns, and floors are of reinforced concrete and steel. Further, some of these buildings also have HVAC systems and self-pressurizing stairwells. This stops fire from further spreading. Also, ventilation is sometimes absent. This is because the roof is also made of non-combustible materials. 

Type 1 applies to buildings over 75 feet tall. It can be a commercial as well as a residential project such as hotels, shopping complexes, apartments, etc. Yes, these buildings are the safest of all, but also they are the most costly to construct. If at any time there is a need for firefighters to enter one of these buildings, their job will be significantly easier.

Type II Construction: Non-Combustible

These buildings are similar to Type 1 yet not as efficient as them. They contain non-combustible walls, columns, floors, roofs, and partitions.

Yes, they have fire suppression systems but do not have a fire-resistant coating.

The roof is made of combustible material. It can be a layer of asphalt waterproofing along with a combustible felt paper covering. This makes these types of buildings more prone to collapsing.

Non-combustible buildings can have metal floors and roofs with masonry or tilt-slab walls. Recently renovated structures like school buildings and malls are constructed in this style. Firefighters in this building will try to prevent a further rise in temperature.

Type III Construction: Ordinary

These are ordinary buildings that can be both old and new. The old ones will have conventional old frames whereas the newer ones can have lightweight roof systems.

They are made of non-combustible materials. However, some of the interior structures such as the floors, ceilings, or frames are constructed with a combustible material like wood. These buildings can either have tilt slabs or reinforced masonry walls. 

They are also known as brick-and-joist structures. In addition, ventilation is possible here, unlike with Type 1.

Ordinary buildings have attics and spaces that increase the chances of fire extensions. You can find this style of construction in houses, schools, or any normal building.

Type IV Construction: Heavy Timber

If you look at old churches, factories, or barns, you will find this type of construction. It is marked by the use of lumber connected with bolts and metal plates.

Furthermore, you will also spot heavy usage of timber. This type of construction was famous in the 1960s, and the buildings are made of combustible material. As a result, they are more prone to fire. But their structural mass makes it difficult for them to collapse.

They also have non-combustible walls and exteriors. The columns and beams are made of wood.

Additionally, they have metal joints that increase the chances of fire spreading. Here, firefighters would require a large amount of work to extinguish a fire.

Type V Construction: Wood-Frame

So far we have read about several types of construction, and now we reach our final category. It is the most combustible one. Until now we have read about buildings having both combustible and non-combustible elements. However, this type uses solely combustible materials for both the exteriors and the interior. Wood is used for frames, ceilings, walls, roofs, and columns.

We all know wood is non-resistant to fire, and that fire can spread in these structures in no time. Wood is also a light substance, so therefore the chances of collapse are also high. It is very difficult for firefighters to manage fires in such buildings, but they are less expensive to build.

By now we have seen all the major types of construction found in our daily life. At Erisa Projects, we hope that from now on, it won’t be difficult for you to guess the type of construction. You can now go about the city looking at construction projects with the eye of a contractor.