Yes, installing new insulation on top of existing insulation is safe. However, there are certain circumstances to consider before installing new insulation over old. Insulation does not last forever; it wears out upon exposure to weather changes, moisture, and other factors. The indicators of damaged insulation include quick temperature changes, higher energy bills, mould, and rodent infestation. From our extensive experience in the insulation industry, we can assure you that installing new insulation over the existing one is perfectly fine. In fact, you do not have to use the same material as in the old one.
This article explains the factors you must consider before starting the process of installation of new insulation over old.
You Must know the Type of Already Installed Insulation
Before adding new insulation material, you first need to know what type of insulation is in your attic. Many homes were insulated with vermiculite in the 1900s. Vermiculite has been known to have asbestos and needs to be tested before any work is completed in the area.
Condition of Previous Insulation
Observe the physical condition of the already installed insulation in your house. In case of deteriorated or infested insulation, the contractors recommend you remove the old insulation altogether. It is unwise to install new insulation on top of a damaged or infested insulation layer. Therefore, please check your old insulation and ensure it does not have the following problems:
Rodent Infestation
Rodents find insulation materials warm and often form their nests inside. This causes substantial air quality and health issues for residents. Installing new insulation on top of infested insulation will waste resources and effort. To check if your previous insulation does not have this problem, physically examine it for droppings, gnaw marks, tracks, unusual noises, and rodent nests. If you find any one of these problems in your insulation, immediately contact an insulation contractor to find a solution. They will likely recommend you remove it entirely and get new insulation.
When Insulation is Moist
In addition to causing mould and mildew, wet insulation can also lead to the rotting of ceilings and roof rafters. Moisture retention or wetness reduces the insulation capacity of insulation. Hence adding new insulation on top of such insulation will also affect the functioning of newly added insulation. If you have wet insulation, look for the cause and find a remedy to fix the current issue so it does not reoccur. Removing the damp insulation and replacing it with dry and new insulation material is better.
In Following Situations, Avoid Adding to Existing Insulation
In case your previously installed insulation is damaged and not performing well, do not add new insulation on top of it. Remove the old and damaged ones and replace them entirely with new insulation.
Other factors like air leaks, ventilation issues, or other problems can affect the performance of your previous insulation. In such a situation, you do not need to add new insulation on top of old rather; you have to fix the air leaks and ventilation issues.
Finally, you should consider if you need to complete any renovations. When you have an insulation contractor going into your attic space, it is easier if they have clear access to complete their work. At that point, it is a good idea to have our experts look at your attic space and give our recommendations! Reitzel Insulation can help you add new insulation over old insulation to fulfil your needs.
Call us today for your free onsite estimate!