Heritage, Health & Sustainability


World Green Building Council

Heritage, Health & Sustainability

Le Lay Architects are specialists in contemporary design of heritage buildings, promoting sustainable design and health and wellbeing. As experts in the conservation and heritage sector, we realised materials and techniques seen in historic buildings have  inherent health benefits. For example, the use of lime plaster can inhibit mold growth which is associated with increased prevalence of respiratory symptoms, allergies and asthma.


Historic buildings are inherently ‘breathable’; they allow the passage of moisture to move from inside to outside, preventing the buildup of dampness in the building fabric. Refurbishment of a historic building requires a comprehensive understanding of the hygrothermal properties of the building fabric. Simply fitting insulation without understanding how this can affect breathability can lead to interstitial condensation and mold growth.


Poor ventilation and design also have a major impact on indoor air quality. Cooking and cleaning is a major source of particulate matter in the home and if the kitchen is not well designed, it can lead to respiratory problems. This is particularly important for vulnerable people who are more likely to spend more time indoors such as young children and the elderly. Getting a good flow of air through the building while minimizing heat loss from drafts is particularly important to human comfort and health.

Materials and Out-Gassing

Modern refurbishments typically introduce building materials derived from petrochemical industries. Many of these are known to out-gas years after construction, emitting harmful chemicals into the air including as formaldehyde into the room. Le Lay Architects are currently looking into low emission materials that are derived from natural sources such as cork, hemp and sheep’s wool. We are developing a specification based on this knowledge to promote healthy lifestyle design.

If you would like to know more about how healthy your house is or want to design a healthier home. Please email us – who knows? it may be good for you.