Willaston Windmill.
The tower mill in Willaston was built in 1800 William Lightbound (b 1770) to replace an earlier post mill, and was constructed by millwright Henry Gardener. At five storeys high it was the tallest windmill every built on the Wirral peninsula.
The mill went under what can only be described as Major restoration work. the owners have truly maintained a piece of the English Windmill History going above and beyond to restore in and outside the mill. This lovely couple deserve a lot of praise bringing this old Listed mill back to life.
Pictures of pointing works and Brick repair/replacements, coming soon!
This Project had a few hand's turn to it. Ourself's and one other company were called in at different times with different views on suitable lime.
the opposing company used Hot-lime , where we wanted to use Hydraulic. With this mill being out in the open, having to take heavy weather year in and out. we knew using Hot-lime would not be a safe approach. Hot-lime is vulnerable in projects where heavy rain and frost are a yearly occurrence.
And with a long drying out time up to several months we opted with Hydraulic. and to be on such a big project with no control over the time frames?
Openly We had no issues with the application and how the hot-lime was applied by the other company. we both wanted to make a great job look good.
The client/owners decided the best option was Hydraulic lime and decided to go with us..
Which We were called back in to finish the lower sections of the mill.
So why did we choose Hydraulic lime on this? It was a matter of timing, season of the year, scaffolding time-frame especially(which costs on this building where expensive), amongst many other factors to take into consideration. One main thing we took into consideration was the joint thickness and depths. this was a big baring on our choice.
Hydraulic and Hot lime? both can be described as serving the same purpose once full set. but both set differently. completely differently. drying out and mixing! and they’re playable texture.
Let us talk a little about hot-lime and Hydraulic. the pros and cons.
So, as mentioned There are many factors that will impact lime mortar drying times. Understanding these factors is essential. In some cases lime mortars could dry too quickly causing the mortar to fail, while in other circumstances lime mortars may never fully cure.
Here are some of the key factors that can influence drying times:
Hydraulic lime sets due to a process called Hydrolysis, which is similar to the way cement mortar sets. This is ideal when you are working in wet areas, as it sets much fasters than non-hydraulic limes, but it is also less breathable and flexible.
Non-hydraulic lime sets as a result of carbonation, where mortar absorbs carbon dioxide from the air in order to slowly and gradually harden. The material has to be damp for this to work, so it needs to dry slowly over a week or two. Highly flexible and breathable, these mortars are popular, but they may never set in environment’s where they are unable to fully dry.
So, as you can see we, why we used Hydraulic lime "based on the environment". with the harsh weather having to keep damping. this can result in frost crack, especially in the harsher environments.
Now, let’s talk about Environmental conditions.
Environmental conditions have the biggest impact on lime mortar drying times. For example, areas sheltered from wind and sunshine will dry more slowly than areas exposed to the elements. It’s important that lime dries slowly, as this allows it to gain a good hard set.
Lime must be protected from strong sun, wind, or hot conditions, or it will likely fail (usually going white and crumbly). A-lot of care isn’t it? The best way to protect lime is to regularly mist spray with water for 3 days (longer if using non-hydraulic lime), making sure it dries very slowly. If you are struggling to keep your lime mortar from drying too quickly, hanging damp hessian in front will help control the curing process.
Lime should never be used in freezing conditions. Ensure you have at least two weeks of temperatures above 5°C before attempting any exterior lime work.
We mentioned about the depth and thickness of the brick. which could have a big sway on your choice of lime product. Also, How thick the lime mortar is that you apply can also have a big impact on drying times, as thicker layers will take longer to dry than thinner ones.
If you have large/deep joints, always allow an extra week or 2 for drying.
So, our honest conclusion about this property.
Whether opting for hydraulic or non-hydraulic (HOT)lime, each type offers distinct benefits and challenges, particularly when it comes to drying times. Factors such as environmental conditions and the thickness of the application play pivotal roles in the curing process, with a slower drying time being crucial for achieving a strong set.
Understanding these nuances is key to preventing premature mortar failure and ensuring the longevity of your construction work. You can navigate these challenges effectively by following best practices such as mist spraying, controlling environmental exposure, and choosing the right type of lime for your specific needs.
Its an argument or debate that is had many times over. the great thing is, both materials serve a great purpose.
Comments