Why do internal doors expand? Introducing the Deuren difference

While some overlook a door as a mere divider between rooms, others understand how integral these components are to the flow, functionality, and aesthetics of a space. Down to the smallest fraction, as minute as a millimetre, each design is carefully considered to fit flawlessly, operate seamlessly, and maintain superior energy efficiency throughout your home. So, what happens when the precise balance you’ve worked so hard to achieve becomes compromised?

In this blog, we delve into the mechanics behind expanding, warping, and swelling wood, and introduce you to the Deuren difference – the superior technical details that preserve the integrity of your unique design, placing our bespoke internal doors in a league of their own entirely.

There’s a common misconception that high temperatures are the primary root cause of door swelling. In reality, drastic changes in temperature, and sudden shifts in the surrounding environment, are the biggest culprits ensuing chaos. Since wood is a naturally porous material, it responds to fluctuations in humidity by absorbing or releasing moisture, causing it to expand or contract. This is when you’ll notice things like doors sticking, difficult latching, or even gaps that form between the leaf and the frame – if the door isn’t properly protected, that is. 

It’s not just moisture that affects stability, either. Prolonged exposure to UV rays gradually breaks down the molecular structure of the wood, drying it out and making it more vulnerable to movement when humidity levels fluctuate.

But why do internal doors swell in winter, more than any other season? In colder months, the temperature difference between indoors and outdoors is at its most extreme. While the climate outside is typically humid, central heating dries the air indoors, causing a sharp contrast that’s far less prevalent in the milder, more stable conditions of spring, summer, and autumn. And when doors and windows are open – even momentarily – the imbalance intensifies, allowing moisture-laden outdoor air to rush in, further stressing the wood and causing it to swell or warp more noticeably.

Even the most seemingly menial details can have a significant impact on moisture content. Grain orientation determines how wood expands and contracts, with quarter-sawn timber moving more evenly than plain-sawn cuts. Meanwhile, kiln-dried wood provides better climate control than air-dried alternatives, and poor post-lumber storage considerations can spell disaster for the material’s longevity. This is before we’ve even considered manufacturing, installation, and maintenance.

As well as ensuring meticulous sourcing, transportation, and storage, we therefore maintain a carefully climate-controlled workshop to preserve the integrity of each curation. But that’s not all. Every Deuren door is also thoughtfully handcrafted using the finest-grade engineered timber. Using multiple layers of compressed wood with alternating grains, the core of each product is significantly more robust – with greater resistance to warping, twisting, and shrinking compared to a non-engineered or hollow alternative. So, unlock greater stability and performance that endures for decades, while maintaining an aesthetically exquisite appeal on the surface.

Once premium materials have been selected, it’s down to the shaping, assembling, and finishing of the wood to determine its long-term durability. Every cut, joint, and component must be expertly crafted with absolute precision to minimise movement over time. By coupling seasoned expertise with state-of-the-art machinery, our engineers guarantee exacting tolerances on every product. And the finishing process is equally crucial. Careful curing allows the wood to settle naturally, releasing internal tensions that could lead to warping, while sealing and protecting every surface safeguards lasting resilience.

Beyond the build, meticulous attention to every precise measurement is incredibly important for performance too. When we approach any project, no matter how intricate or complex, we understand how each bespoke dimension will sit within a space, respond to its environment, and impact other components.

Even the slightest misalignment can cause the leaf to sit incorrectly within the frame, disrupting the seamless flow of movement and compromising humidity control. Insets and detailing, if not perfectly positioned, can create unnecessary tension, increasing the risk of long-term instability.  And when these subtle stresses compound, they can cause your door to distort, shift, or resist natural changes that would otherwise go unnoticed. What’s more, while interior doors do not come into direct contact with the external environment, they can still be affected by fluctuations between the indoor and outdoor climates, which can subtly influence humidity levels within the home and cause wood to absorb excess moisture and swell.

With our expert installation, every element is aligned with exceptional precision, preventing the risk of unnecessary strain, balancing indoor and outdoor climate discrepancies, and ensuring the door functions exactly as intended. From frame positioning and hinge placement to clearances that account for natural settlement, each detail is considered to support the long-term function and integrity of your bespoke product. So, your door remains as refined in its movement as it is in its aesthetic, year after year, no matter how the environment changes. This level of care can’t be found anywhere else.

Bespoke doors are defining features that elevate the architectural integrity of your home. But when products warp, the impact extends far beyond aesthetics, and what was once the linchpin of harmonious living can quickly become a daily frustration. 

You may find yourself wondering, “Why are my internal doors sticking?”, facing difficulty opening or closing each leaf and even compromising the overall security, safety, and energy efficiency of your space. Of course, there’s then the painstaking process of realigning, repairing, or replacing the door – a costly and headache-inducing exercise that adds to an already stressful process of renovating or self-building. Luckily, it can be avoided by selecting a premium quality product from a trusted bespoke internal door specialist.

With a hard-earned reputation as the UK’s authority on doors, we’re proud to be recognised for the unmatched quality, aesthetic excellence, and technical superiority of our products. So, you’ll be glad to know our doors require minimal care and maintenance to keep them performing at their very best. As with other aspects of your home, small, routine steps – including wiping the leaf with a damp cloth, polishing hardware with non-abrasive materials, and cleaning and buffing glazed panels – will help them look and work like new for years to come.

Our hinges are also adjustable in three dimensions, allowing for tweaks if your property’s structure shifts over time. And, for timber-finished doors, speak to our experts about annual wood care creams and re-lacquering, for continued water-repellance and protection against dirt.

Crafted for durability and elegance, Deuren doors are unlike any other. Sourced from a single batch of timber, our core construction consists of multiple layers of engineered hardwood to deliver consistent strength, durability, and resistance to warping, even under the toughest environmental conditions. But just to be absolutely sure, we rigorously test every door before giving it the coveted Deuren seal of approval.

As a British manufacturer, we take great pride in ensuring every Deuren door meets the highest standards. The kind that sets the bar for the rest of your project. Our meticulous quality control process ensures only the finest materials are selected. Then, by overseeing every stage of production in our Yorkshire workshop, this unwavering consistency can be maintained at every stage, so each door not only embodies exceptional design but also delivers lasting durability and performance, making a bold statement for decades to come.

Ready to unlock the potential of your project? Talk to our experts about bespoke internal doors that perform as impeccably as they look, expertly crafted to match your boldest ambitions.