Internal weather

Internal weather

Internal weather: conveying moisture from source to symptom.

The solution is downstairs, turning things down and operating our homes efficiently. Misty windows are a cue to break old habits, the response, closing internal doors and operating windows.

The current air movement model does not reflect how air moves through or around the interior of a building. Pressure testing is method by which to achieve a compatible number. Air is not blown in or out it is sucked through.

Internal weather: cross ventilation stratification and convection.


Black mould only grows on pure clean water. Condensation ocures when warm moist air meet a cold vapour impermeable surface, such as a glass window pain or other vapour barrier such as cement render, vinyl paint, PVA or ‘damp stopper’.  A breathable and hygroscopic thermal envelope will reduce the risk of condensation.

Internal weather: black mound only grows on pure clean water, condensation.


This property has had scaffolding up four times in the past year. Every wasteful attempt to respond to the householders reports of water getting in further exacerbate the problem by stopping it getting out. And yet no budget is available for a knowledge-led approach that would provide the information this householder need to prevent them or the contractor from further damaging the thermal envelope.

If we can't find it we'll invent it

Cross ventilation stratification and convection. Tackle the large holes to exposes the small, if its not universal it won’t work. Operating windows and doors with operable latches and locks. Flexible decorators caulk and the expanding foam applicator gun, versatile and indispensable for junctures, chimneys, floor boards and service voids. Retrofitting vinyl draught strip and the benefit to internal doors. Affordable and attractive magnetically secured polycarbonate secondary glazing is an easy and affordable way to draught proof whilst also slowing the convection of cold air falling away from the window.

How what we do in our homes and to them affect how they behave, causing damp.

Internal weather
How air circulates around and through the home, conveying moisture from source to symptom.

Thermal envelope
How the thermal envelope was originally intended to perform, what went wrong and how to put it right on a budget.


Advice and consultancy
Damp pathology
Trouble shooting tutorial, learn how to remove the discord to create harmony with simple no cost and low cost strategies and interventions that tip the balance back from cold and damp, to a warm and dry cosy home.