You simply insert the pre cut pieces inside the gutters.
Reasons not to plastic gutter.
Most plastic is also susceptible to the cold so if you live in a climate that gets extremely frigid winters or you opt for lighter grades of vinyl you could find your gutters cracking in the middle of winter just due to the cold.
One area in which plastic guttering cannot match cast iron and aluminium systems is on longevity as upvc house gutters can sometimes become brittle from years of uv light exposure.
The foam allows water to pass through it into the gutter while blocking leaves flowers twigs and other debris from entering the gutter system.
Plus ladders will not dent the material and any blemishes on the surface will not be visible.
It s the most common reason for overflowing gutters.
Foam is easier to install.
Upvc is though highly resistant to water and will not freeze or corrode over time.
While not a permanent fix you can generally get another season or two out of the gutters as long as the damage isn t extensive by applying a silicone or rubber gutter caulk or sealant.
In the shape and size of gutters plastic is stronger than the metal alternatives.