Custom Door Sills

Door thresholds made of natural stone

A natural stone door sill creates a sturdy, durable, and neat transition between the exterior and interior. It helps drain rainwater, protects the bottom of the door, and gives your entryway a polished finish.

At Renier, we craft fully custom door sills from Belgian Blue Stone and other high-quality natural stones.

Custom-made door threshold in Belgian blue bluestone
✓ Fully customized
✓ Strong and durable
✓ Direct from the producer
✓ Suitable for new construction and renovation
✓ Belgian Blue Stone from our own quarry
✓ Durable finish for any facade

Why does an exterior door need a threshold?

A door sill may seem like a minor detail, but it serves an important function. It forms the transition between the facade, the exterior door, and the floor or pavement. Without a properly installed sill, rainwater can more easily seep inside, and the bottom of the door will be subjected to greater wear and tear.

Water Drainage

A properly installed threshold helps drain rainwater away, preventing it from seeping in under the door.

Sealing and Insulation

The door sill helps seal off the space under the door against drafts, cold air, and moisture.

Door Protection

The bottom of a door is susceptible to moisture, dirt, and wear and tear. A threshold helps prevent damage.

Sustainable Transition

A natural stone threshold is strong and can withstand daily use, foot traffic, and the elements.

Neat finish

The threshold creates a seamless transition between the exterior and interior, in both modern and traditional homes.

Added Value for Your Home

Natural stone exudes quality and retains its beauty for years, providing a durable finish for your facade.

Why choose a natural stone door threshold?

Natural stone is often chosen for exterior doors because it is strong, durable, and timeless. Belgian Blue Stone, in particular, is especially well-suited for door sills: the stone is wear-resistant, frost-resistant, and complements almost any facade style.

  • Sustainable: Natural stone lasts for years and can withstand heavy use.
  • Weather-resistant: Suitable for rain, frost, sun, and temperature fluctuations.
  • Easy to maintain: Easy to clean and resistant to everyday dirt.
  • Timeless appeal: suits modern, country-style, and classic homes.
  • A solid foundation: Ideal as a transition between the facade, door frame, and floor finish.

Flat door threshold or door threshold with a raised edge?

When it comes to door thresholds, the choice is often between a flat threshold and one with an upstand. Which type you need depends mainly on the door profile, the desired waterproofing, and how the door is installed.

Flat door threshold without an upstand

Flat door threshold

A flat door threshold has no raised edge. Therefore, the top remains completely flat.

  • Sleek and modern look
  • Easier passage
  • A popular choice for modern doors
  • Suitable when the door profile itself provides the seal
Door threshold with raised edge

Flat door threshold with a raised edge

A flat door sill with an upstand has a small raised edge at the back. The door profile fits against or over this edge.

  • Better protection against rainwater
  • Proper fit with the door frame
  • Often chosen when waterproofing is important
  • Helps prevent water from getting inside

Why is there sometimes a recess in a door sill?

For some exterior doors, part of the door sill is locally shaped so that the door frame fits perfectly against the natural stone. In the industry, this is called a "Place the pillow".

This recess ensures that the door can be installed correctly and fits snugly against the threshold. It also often helps to improve rainwater drainage and create a durable seal between the door and the natural stone.

The shape, depth, and position of the cushion depend on the type of door and the selected door profile. For this reason, this process is always custom-made.

Door threshold with cushion

Door threshold with a continuous cushion

The cushion ensures a better fit between the door frame and the threshold. This gives you a finish that’s both technically sound and aesthetically pleasing.

Door sill with a cushion 5 cm from the edge

Door threshold with a custom-made cushion

The position of the cushion can be adjusted according to the door supplier's technical specifications, for example, at a fixed distance from the side.

What is a miter cut on a door sill?

Sometimes a door sill needs to connect to a foundation plinth, a door frame, or another natural stone element. To ensure that this connection is neat and seamless, a miter joint is used.

A miter is a beveled cut at the end of the threshold. This ensures that both natural stone pieces fit together neatly and prevents visible end grain. The result looks more refined and provides a professional finish for the entire entryway.

Whether a miter cut is needed depends on the construction of the facade and the chosen natural stone finish. Our staff would be happy to discuss this with you.

Example of a mitered door threshold

Example of a door threshold with a miter joint

How do you choose the right door threshold?

The right door threshold depends on your door type, the facade, the floor construction, and the desired finish. Not sure which one to choose? We’ll work with you to determine which option is best suited for your needs.

New Construction or Renovation

Renovation projects often involve working with existing openings. Thanks to custom fabrication, the threshold can be adapted to fit them.

Flat or with a raised edge

The choice depends mainly on the door profile and the desired waterproofing.

With or without a pillow

Some door profiles require a local cutout in the threshold to ensure a proper fit.

Belgian Blue Bluestone Door Sills in Practice

Door sills made of Belgian Blue Stone complement many different home styles. They combine technical quality with a natural and timeless look.

Need a door threshold for your project?

We’re happy to help you choose the right option, dimensions, and finish. Thanks to our in-house production, we supply high-quality, custom-made door sills to contractors, architects, and homeowners.

Frequently Asked Questions About Door Sills

Which type of natural stone is suitable for a door sill?

Belgian Blue Stone is one of the most popular materials for door thresholds. The stone is strong, durable, weather-resistant, and has a timeless look.

What is the difference between a flat threshold and a threshold with an upstand?

A flat threshold has no raised edge. A threshold with an upstand has a small edge at the back that helps ensure a proper fit with the door frame and provides a watertight seal.

What does it mean to kiss at a doorstep?

"Cushioning" means creating a recessed area or lowering the threshold in one spot. This allows the door profile to fit more snugly against the natural stone.

What is the purpose of a drip groove?

A drainage groove prevents water from flowing under the sill toward the facade or door. This is important for a durable and proper installation.

When is a miter cut necessary?

A miter cut is useful when the door sill needs to fit neatly with other natural stone elements, such as foundation sills or door frames.

Can a door threshold be custom-made to exact specifications?

Yes. At Renier, door thresholds are custom-made to the desired length, width, thickness, finish, and technical specifications.

Are his door thresholds suitable for renovation?

Yes. Natural stone door sills are ideal for renovation projects. Thanks to custom fabrication, existing doorways can be finished neatly and durably.

What is the lead time for a custom door sill?

The standard delivery time is usually about two weeks, depending on the selected model, finish, and production schedule.