As our sashless windows have flush infills all the way around the inner frame we often get asked how to install this type of window. Below is a cross section of the jamb and head fixing detail in a commercial double glazed frame. Note that the fixing adaptor you are using may be different to what is shown as we offer several fixing adaptor options. To fix off the jamb we recommend drilling a hole through the flush infill slightly larger then your fixing. This hole will be covered once the sashless team comes to fit the sashless insert. More care needs to be taken when fixing off the head as the sashless insert does not fully cover the flush filler. The head fixing must be counter sunk and at the position shown below. Again, this fixing will be covered by the sashless insert. We do not recommend putting a fixing through the sill as this can cause water issues.