The threshold is the bottom part of a bifold door frame that you step over. Plan it with the finished indoor floor and outside surface, especially if another contractor will complete flooring or patio work.
Put the levels on one drawing
The drawing should show the finished indoor floor, the threshold and the finished patio or decking. Include the planned floor covering when discussing heights; a bare concrete floor is not the finished floor. The door supplier and the person completing surrounding work need the same agreed information.
Compare the actual threshold options
Bifold systems can have different threshold arrangements. Ask which version is proposed and how it will feel when you step across it. A photograph of another installation cannot confirm the detail for your opening. Ask for a side-on drawing of the selected door and floor so you can see how they meet.
Show where water will go
The design needs to account for water leaving the frame and water on the outside surface. Ask for the frame's drainage route to be shown. The agreed design should also show whether an outside drainage channel is needed and where its water will go. A channel beside the door is only one part of the arrangement. Patio or decking work must keep the agreed route clear.
Agree who completes each part
Record the door fitting work alongside any work by a builder, flooring contractor or landscaper. Ask who prepares the opening, installs any outside drainage and finishes the surrounding surfaces. The written scope should show what is included and what is separate. If planned levels change after the survey, tell everyone involved before the work continues.
Discuss access early
Tell us how the entrance will be used and whether a step, handle or narrow passage would be difficult. Ask for the proposed threshold and the width you can walk through when the doors are open. A "low threshold" label alone cannot tell you whether the entrance will suit you.
Questions
Can the inside floor and patio be level?
That depends on the chosen door and site. Ask for the proposed floor and drainage arrangement before agreeing the levels.
Does every bifold need an outside drainage channel?
The design must establish what is needed for the site and door. Ask for any channel and the water's route to be shown.
What should I do if a floor level changes?
Tell the door supplier and other contractors before the work continues. Agree any revised drawings and changes to the fitting work in writing.
Send photos, approximate opening sizes, your postcode and any floor or patio plans for an initial estimate. Explain any access needs. After you accept the estimate, the final survey checks the details needed for the order.
