Today at MacLennan’s head office, staff underwent a training session with MD Ian MacLennan on the use of and benefits of traditional techniques when undertaking work on a historic building.

During the training Ian taught the history of lime, lime plasters, wattle and daub and the uses of these techniques throughout history, such as the turning point of Eddystone Lighthouse where hydraulic lime was used for the first time and the resurgence of lime based techniques in the 80’s.



Later on the staff watched videos of Ian creating lime putty from scratch, in a kiln he created at MacLennan’s head office when we used to create and sell lime based products.

MacLennan make sure that all staff are trained in this way so as we can approach the delicate subject of repairing a historic building with a conservationist nature in mind, where it applies.

Here we have MacLennan operatives installing an internal cavity membrane waterproofing system on top of closed cell insulation, including waterseal tape detailing around the internal pipe penetrations and overlaps of each membrane sheet. Open cell Insulation was then applied over the membrane.

Internal Waterproofing Systems such as this one, especially when combined with external waterproofing and sump systems ensure a watertight finish to any property.

Have a look at our “New Build Basement Waterproofing, Chesham, Surrey” Case study for an in depth explanation into the use of this system with Datasheets and 3D details, or our cavity membrane system page for an overview of the system and its benefits.

Here is a MacLennan operative sealing around service ducts on external waterproofing, it is important that service ducts are properly sealed because most water ingress occurs at the details.

  MacLennan operatives completed a course in safe manual handling (level 2) today as part of our regime to make sure that our operatives are fully aware of the dangers a work situation can impose on them, MacLennan are dedicated to providing training that furthers both the interests of our clients and our operatives on a regular basis.

Like all waterproofing and roofing contractors MacLennan have a tough time trying to apply waterproofing systems in Winter conditions.

Note to contractors, clients and project managers. If you are planning a roof or deck then do it in the spring / summer and hope it doesn’t rain.

All waterproofing and flat roofing systems require reasonable weather.

A responsible contractor will not even attempt to install if the temperature is below 5 degrees or if it is not 3 degrees above dew point. Relationships may be strained by a lack of progress on site, and then on the first day of reasonable weather every project manager will expect that they are next on the list for attendance, when in all likelihood a good busy contractor, will have a number of delayed projects and all for important , demanding clients who are desperate to complete their work and get there building dry. This is a problem shared by the whole industry, which leads to bigger problems when waterproofing contractors carry out installations in inclement conditions to keep the client happy, and then have a failure / leak as a result.

If you must programme work for Winter months remember the cost of a leak will be far more than the cost of a delay.

The golden rules are that work must not proceed unless :

• Temperature 5 and rising Temperature 3 above dew point, no damp on surfaces.
• Generally it is not possible to apply adhesives, primers, coatings for at least 24 hours after rain. It can appear dry and sunny but the dew point can still be very high in conditions of high relative humidity.

Remember if the contractor is not installing he is not earning, so he is just as motivated as you are.

MacLennan do have cement based systems for wet decks but not cold and Polyurethane systems for application when quite cold but not wet. Nobody has a system for cold and wet decks.