Flat Roofing - General

Do flat roofs last longer than slanted roofs?

Traditional pitched roofing, such as tiles or slates, has exceptional longevity if maintained correctly. Whilst some pitched roof materials will physically last longer, pitched roofing can be difficult to maintain and gain safe access when compared to flat roofing.

What are common flat roofing problems?

The main issues we find are standing water, poor falls, blocked outlets, and inadequate detailing. 

This is likely down to either bad install and design, and no maintenance being carried out. 

At Tremco... 

Why are flat roofs common on larger commercial buildings?

Due to weight loading, flat roofs are a lightweight construction, meaning less money spent on structural support. A flat roof’s overall system depth is generally thinner and more thermally efficient maximising building height. System application can be easier and faster than some traditional alternatives. Flat roofs are more accessible and provide suitable grounds for roof top plant or other building services.   

How do you calculate the area of a flat roof?

Width by length including vertical upstands.

Why do they put stones on building roof tops?

To ballast down loose laid products such as membrane systems or inverted roof insulation. Ballast can provide additional protection to the waterproof membrane against UV degradation, freeze thaw cycles and intense climatic conditions such as extreme heat or hail. Burying the membrane with ballast when future roof access and regularly maintenance is impractical can also help increase the life span of the proposed roof covering. Ballast can reduce health and safety issues associated with standing water, ice formation or slippery surfaces. Some clients may require a fully non-combustible surface finish and ballast is a cheap option. There is a case for temperature control within buildings, but I’ve never seen proven test data.  

What is the best system for a flat roof?

Complete conjecture. Suitable system is subject to the roof design, surrounding conditions, client requirements, building control compliance, health and safety concerns, warranty period, compliance requirements, weight, aesthetics etc. etc.  

How many layers of roof can you add to a flat roof?

Subject to the proposed system and load strength of the supporting structure.

What are the Solutions for Damaged Commercial Flat Roof?

Some “damage” may be repairable. Full refurbishment is subject to survey and roof condition. We always aim to overlay (cheaper) but the existing conditions could be unfeasible.  

How to find the best roofing material for a new building?

NBS Source, BIM Library, BBA website, industry bodies, trade shows, trade associations, press release, word of mouth, Google search and reviews.