When Does Wood Contract and Expand

Again, a word of warning. We can predict the movement in a large amount of wood with a high degree of accuracy. It is not possible to accurately predict the movement of a single piece of wood. Some of the variables to consider: Jolts and pitch pockets, if any, extend through fewer boards Think about the details of your trim and think about how they will react if the wider assemblies shrink. With a widely bonded material, slightly higher MC values may not be acceptable. If you are installing a wide material, it is a good idea to contact your supplier in advance and let them know that the MC of the material should be within the range you specify. As a last resort, you can dry the wood in your store if the workshop`s EMC is low and removal problems occur before the wood is installed. Wood moves along its entire length, but the amount is negligible and can almost always be ignored. Also consider the season. The wood shrinks to its smallest size in winter and swells to the maximum in summer.

Winter wood projects will expand; Wood projects in the summer will decrease. In the spring and fall, remember that wood expands half of your total movement permit and pulls the other half together. Stove-dried hardwood usually leaves the oven for almost 6% MC (10-12% softwood). But all the oven-dried material gets used to the surrounding EMC levels. The main advantage of oven-dried material is that it is usually heated to at least 130 degrees in the oven, which stops any insect activity and also „fixes“ the juice in softwood coniferous woods (juice in an air-dried resinous material can bleed out of the board after installation, especially when indoor temperatures rise in summer). I was wondering if you could advise us. I installed some 3 1/4 prefabricated maple floors on my main floor. I did this during the wet months of the year and the air conditioning was not working. We had a long, dry winter in Ottawa, and the gaps in my soil are huge.

Some at 1/8 inch and pick up all sorts of things out there! As the humidity increases, will they expand? Or maybe it`s permanent? I also thought about sanding them with a load of oak dust paint and sealed with a water-based sealant. Rught now with the gaps, he looks so rough. Below is the basement with unfinished blankets and fresh, cold air for the oven. Thank you! so disappointed. By the way, I have been living in my house for over 30 years, and the only heat we have is a wood stove (6500 degree days in winter – I burn 6 cords of wood). Constant temperature fluctuations can damage wooden furniture due to expansions and contractions. After several extensions and contractions, your furniture begins to deform, which can lead to more problems. Hello, I want to use wood (wood) for the construction of wooden items in my home, how will I know if this wood is about to be used, has little or no shrinkage or swelling of the movement) due to the relative humidity of the environment, since the wood is hydroscopic? I am drying my house because of water damage. Is it possible that the wood can be overdried? If the wood is already installed (don`t worry about its expansion), can the MC drop to 0% without risk? Will a 0% MC expose wood to a higher fire risk? As with doors, this movement in the floors is almost noticeable in the seasonal changes between winter and summer. In the summer, your home is open, there is a lot of moisture in the air and the wood in your floor is completely expanded as it absorbs moisture. Good article Carl! A few remarks: What you call edge grain or VG wood (vertical grain) is usually called quarter sawn and sold, at least in hardwood. There is no doubt that it is much more stable than plainsawn (whether you calculate flat grain or tangential).

EMF helps us understand the response of wood to relative humidity, whether it shrinks or expands. For carpenters and carpenters, EMC is more useful than HR. The simplified diagram on the right shows the EMC values of the wood during storage at the specified humidity and temperature. In my region, for at least 150 years in high-end work, flooring has been laid against skirting boards without shoes last. The base is installed first, and the flooring is firmly scratched on it. Despite what your type of lazy or ignorant flooring says, there is no gap even after years of fluctuating humidity and repeated sanding or scraping. This is because when the final grain of the flooring meets the wall, the movement of the flooring is essentially zero with the grain and where the edges of the flooring have an expansion of 1/16″ or less (oak 2-1/4″ t + g) meet the wall, because the flooring is attached to the basement and each room expands and touches – not the whole floor as a unit. I only saw unacceptable spaces between the boards when the flooring was very poorly dried or wet before installation, and the only time I saw a floor loop due to the expansion was when there was a big leak or flood or when the flooring was laid on really green concrete. When the material supplied with an unacceptable MC is installed or the humidity range in the structure exceeds the typical values, the movement of the wood increases – and can cause problems even with well-designed cladding details. It should be noted that the material of the panels (plywood, MDF, composites) moves at about 1/10 of the solid wood rate.

For all intents and purposes, thermal expansion and wood contraction is not a problem. However, warmer temperatures accelerate the exchange of moisture in the wood. Moisture exchange occurs faster at warmer temperatures, but there is no heat movement of the wood worth measuring. Use the Frame and Panel construction. The panels can be made of plywood or solid wood with a raised midfield. Most people like the appearance of raised panels better. If you use solid wood panels, DO NOT stick them on the frame. The plate must be able to float freely and change the dimensions. A small adhesive stain in the middle of the width keeps the plate centered.

This side table by Richard Slosky shows a way to attach a table top and at the same time expand and contract with changes in moisture content. Small L-shaped „buttons“ are screwed to the bottom of the table top, while a slot extended inside the table skirt picks up the button leg. As the top expands and contracts over time, it can move without forcing carpentry or table top, making it last for many, many years. My outdoor test table (cypress wood with minimal finish) has never been in the snow. Let`s see how difficult it is pic.twitter.com/GEqyahEsk4 but this is just a brief overview of the issue. There is much more to know about how cold affects wood applications, how wood expands in winter, what happens to wood when it is wet, what are the common things we can expect when wood is cold. In addition, how to cope with the expansion of wood. So, in this article, we will look at them all and try to find answers with my experiences.

We have problems with the extension of our equipped kitchen cabinet doors. The doors are shaker-style doors and are made in Italy (although the manufacturer`s brochure states that their kitchens are made in British factories themselves). The structure of the frame consists of solid ash and central ash plates plated on MDF. Within 3-4 weeks of installation (May 2017), we noticed a movement of the doors and assumed that adjusting the hinge would solve the problems. Over time, it became clear that wood expansion was the problem. The kitchen was installed in our holiday home by a qualified independent craftsman (advised by us at the time of purchase). The large national company refused to inspect the kitchen because it did not carry out the installation. They say that the cause of the expansion (and very slight contraction in winter) is due to the local conditions of humidity and humidity. Most of our doors get caught when closing or do not close at all. Our previous oak kitchen in this house gave no movement problems. We have been pleading our case for several months, but the manufacturer-retailer (same company) refuses to solve the problem.

For the record, we believe there have been other similar complaints. We are of the opinion that the materials used are not suitable for this purpose. They indicate that the wood used is kiln dried and stored in the right conditions, and then made in Italy. The doors have been pre-assembled on the units upon delivery – the doors fit perfectly to the original. If the information they gave us is correct, should the doors move so far that they can`t close them? Originally, a space of 3mm was allowed between the doors. As we are at an impasse, we would be grateful for any information you may give us. Thank you John & Ann Hearnshaw Can you comment on the effects of wood cryotherapy? There are a number of services that suggest this as a method (and offer expensive) to give the „new“ wood the desirable properties of old wood. .