Can I add New Insulation over Old Insulation without Insulation Removal?
Old insulation removal from attics is a common enquiry however it may not always be necessary to do so. The traditional reasons for insulation removal from attics are damage caused by water, attic infested with rodents or damaged caused due to fire.
When a house is constructed there is always some or the other existing old insulation present in the attic. The object is to bring the attic to a R-38 rating and rather than removing Insulation is added to the existing one. The old existing insulation may have debris, could be dusty and tattered – and if it does not have the contents like asbestos or any unsafe material – new and fresh insulation is installed over it. The material in the old insulation should not have a chemical reaction with the insulation material. The old insulation removal cost is saved and also serves as a base for installing new material over it.
It is only rare cases when insulation removal is actually required. In such an instance the fiberglass is removed by carefully rolling it back before it is packed in bags and taken away from the attic.
The next step of an insulation removal is to take away the material blown that requires a vacuum large enough to remove all the blown material. The vacuum should be kept outside the home – creating pressure in the attic area. The objective is to let no debris enter the home environment.
The entire process is tedious, labor intensive and time consuming at the same time. Therefore, before insulation removal experts are called in they should be given ample time to complete the job. Insulation Removal experts generally charge per square foot. Before hiring them one should take a quote from the main office of the insulation removal experts.
Remember that there is one big NO to the above solution – that is ; NEVER add new insulation over old insulation IF it is ‘WET’. As soon a Insulation is wet call the experts to see if it can be repaired , if not hire insulation removal expert , before it catches mildew, mold and ends up destroying expensive roof by rotting of ceilings or rafts .
Even if you hire insulation removal experts – here are some tips to keep in mind always to be followed much before you add new insulation over old:
- During insulation removal – rolled insulation is not supposed to be tacked down to avoid it from flattening or squashing. This also reduces the R-value.
- Insulation is to be perpendicular when rolled out to the joists. Rolls that are unfaced are the one to be used.
- Instead of Insulation removal over old insulation – one can install three types of insulation such as : Batt, rolled or blown loose fill made of cellulose or fiberglass.
- Avoid old insulation and add new insulation over it – however make sure that the ‘Faced’ insulation is not on top of the old insulation in the attic. The insulation in an attic should be without a face. The face or vapor retarder inserted between the layers of new insulation can easily trap moisture. The facing should be faced towards the drywall of the attic. If not – then it is better that you get insulation removal done.