The soft rod type is composed of breathable material which allows for the passage of air and water. This type of rod is very flexible and it can be used to fit different sizes of gaps. In fact, it can also be used in filling up irregular gaps which has a variable width. The reason for this is because the thick diameters of the rod can be readily forced to fit in to the narrow gaps that are found within the wide joints. This type of rod is very suitable for indoor applications wherein water resistant as well as airtight seals will not be required. Even if they adhere to air and water, they will form a perfect backing when the sealants will be applied. They also do not bond with the sealants hence they ensure that bonds only occur between the building materials and the sealants.
There are plenty of benefits when one uses the soft rod in sealing construction joints. The very obvious advantage of this type of rod is that they can be installed easily. The flexible nature of the product allows them to fit easily into the joints or fissures without the use of excess force. They can also easily bend in order to take the shape of the joint which needs to be readily filled up. This particular application is almost impossible when one uses closed cell rods. The builder will also be able to cover up joints with different widths very easily.
There are also a few limitations that one will encounter with the use of soft rod when filling up the gaps. One major disadvantage of this type of rod is that the worker cannot use the soft rod in filling gaps in outdoor projects. The soft backer rod will usually allow moisture and water to pass through. It is for this reason that the product is not efficient when one will need to form a seal that is airtight. They are also very much vulnerable to heat. For this reason, they cannot be used to form well-insulated seals. These conditions will require the worker to use the other option which is the closed cell version when sealing the joints. Most dealers that are supplying backer rods will advise their customers on the practical type of backer rod to use depending on their unique application.