Home Improvement

Why Your Front Door Won’t Lock When It’s Hot Out?

Image source: Kawin Ounprasertsuk / Shutterstock.com

Ever wondered why the front door won’t lock in hot weather, is there even a connection? After all, it was fine yesterday and the day before, right?

You are not alone in your troubles of being locked outside on a hot summer day. In fact, in this blog post, you will learn the reasons why the door won’t lock as well as some practical ways of how to hopefully fix it when it happens. So, wipe the sweat from your forehead and read along.

Does hot weather affect door locks?

The culprit behind why the lock won’t work in the heat lies in a process called thermal expansion. When temperatures soar, materials like wood and metal become warmer and expand. The door and its frame may experience changes due to this expansion, as different parts are affected.

An example of this is wooden doors. When the air contains more moisture, wooden doors soak it up, causing them to expand. This expansion can cause the door to no longer fit correctly within its frame, resulting in misalignment. As a result, the locking mechanism may have difficulty functioning correctly, resulting in an aggravating situation where your front door cannot be locked.

In the same way, uPVC doors, though less susceptible to moisture than wood, can still be affected by heat. They may also enlarge when exposed to high temperatures, although not as much as wood. However, even a small amount of expansion in uPVC doors can result in issues with alignment, preventing them from locking properly in hotter weather.

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How do you know if your door is hot? Keep an eye out for these warning signs: difficulty locking, sticking or jamming, and warped or uneven surfaces. Based on these signs, it may seem that your door is affected by high temperatures and may need to be modified for better functioning, particularly in hot weather.

Let’s examine each of these indicators more closely.

  • Difficulty locking – One of the most noticeable signs that your door is affected by heat is the difficulty in locking it. It likely has misalignment issues with the lock mechanism due to thermal expansion. Try to remember back if this has happened before when it was hot. If it has, then you know the reason;
  • Sticking or jamming – Another telltale sign of heat affecting your door is if it starts to stick or jam when you open or close it. The expanded materials can cause the door to become slightly misaligned with the frame, resulting in friction and resistance when you try to operate the door;
  • Warped or uneven surface – As the wood takes in moisture from the surrounding air, it may expand in an irregular manner, resulting in a distorted or bumpy surface. This can cause the door to seem bent or have sections that stick out or sink in, making it a challenge to properly fit into the frame.
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How do you fix a front door that won’t lock from the heat?

If you find yourself facing a front door that won’t lock when closed, don’t panic. Here are some immediate solutions and temporary adjustments to get your door back in working order:

  • Make sure there are no objects blocking the door – Examine both the door and its frame for any visible obstacles or debris that could be causing the lock to not function correctly. If you come across any, remove them;
  • Take care of the misalignment – You may need to lift or push the door to properly align the locking mechanism if heat expansion has caused a misalignment. Slightly adjusting the door while trying to lock it could realign the components and solve the issue;
  • Apply a silicone spray or graphite lubricant to the lock – This will, at least, temporarily decrease the friction and ease the mechanism, so you can operate it;
  • Readjust the strike plate – if you can’t lock the door from either side, then loosen the screws on the strike plate. Afterwards, move the plate until the latch aligns correctly and you can once again lock or unlock the door;
  • Install some weatherstripping – When you put this contraption around your door frame, it will create a nice seal between it and the door. You will notice the difference during the winter, but even more so in the summer. It will reduce the high temperature and humidity a great deal.

Locked out in the heat?

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Locked out in the heat?

Stay cool with our emergency locksmith services!

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How to protect your front door from the sun

Check out the tips we provided below that will help shield your door from the heat and minimise its impact as much as humanly possible:

  1. Maintain proper ventilation – Proper ventilation inside your home during the summer days is essential when you want to reduce the heat buildup around the front door. Consider keeping interior doors open for better air circulation and to prevent trapped heat from affecting the door’s materials;
  2. Keep your doors closed during the peak sunlight hours – The timespan between late morning and early afternoon is where you get the most sunshine and hence when it’s the hottest. So, when you close the blinds of curtains, you will significantly reduce the heat;
  3. Install some shades or awnings – There are two benefits when you do this. One, you enhance the appeal of your home and two, they will give you and your locks the much-needed shade.
  4. Use materials that are heat-resistant – Composite doors are a great example of this. They maintain their shape and size in varying weather conditions from very cold to very hot. Metal or fibreglass doors also don’t warp or swell as much as regular wooden doors;
  5. Apply a sun-resistant coating – There’s a wide plethora of coatings and sealants in today’s market that minimise the effects of the sun’s UV rays and keep your doors from, fading, cracking or warping. That last part is especially important as far as your lock is concerned;
  6. Regular maintenance of the door – Always keep a close eye on your door and fix minor problems as soon as they arise.
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Call an emergency locksmith

If you can’t troubleshoot this problem on your own, or find that it keeps happening again and again, maybe you should consider hiring professional assistance. Here at Fantastic Services, we work only with fully-equipped and highly experienced locksmiths to give you:

  • Immediate response – We have a 30-minute response time, day or night, so you’re never locked out or in for long;
  • High-quality workmanship – We offer a 12-month guarantee on all services we perform on your property;
  • Transparent pricing – We provide clear and competitive pricing, so you know exactly what to expect before the work even begins;
  • A variety of services – From changing existing locks to repairing them, handling emergency lockouts, and extracting broken keys, we cover all your needs.

Still struggling with the door lock?

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  • Difficulty locking, sticking or jamming, and warped surfaces are telltale signs of thermal expansion and thus why your door isn’t locking in hot weather;
  • To restore some functionality in the locking mechanism, check for obstructions, lift or push the door;
  • Install awnings or apply a sun-resistant coating to shield your door from sun damage and prolong its lifespan.
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