Thermarich Lumber

What is Thermarich Lumber?

Thermal modification of wood is a natural process of “cooking” the wood in oxygen-free ovens to temperatures over 400 degrees. This is an excellent alternative to chemically treated lumber. The thermal modification method changes the wood’s cellular and molecular makeup, removing all the wood’s organic compounds.
This process makes it so the wood can no longer absorb water, reducing the ability of the wood to expand or contract. Which means the wood is highly durable. Removing the ability to absorb water enhances the rot resistance of the wood.
Thermally Modified Wood | Edrich Lumber

Benefits of Thermarich


It cannot be warped or deformed by water due to the natural process that prevents water from being absorbed into the wood.


This process prolongs the life of the wood, which decreases the need to redo your projects by up to 25 years or more!

Free of Chemicals

The thermal modification process uses heat only to cure the wood.

Stages of Production


The temperature increases, removing sap and pitch in the wood. Steam is introduced to the wood making the moisture content go from about 20% to nearly 0%.


This phase is where the water breaks apart from the wood due to the higher temperature heat. Oxygen is completely removed, and the thermal modification process has begun.


Steam is reintroduced to help decrease the wood temperature and maintain dimensional stability. Resulting in a wood moisture content of 4 to 6%

Common Questions & Answers

Kiln Dried Wood is wood that is dried out to a 5%-14% moisture content and does not change its molecular structure.

Pressure Treated Wood uses fungicidal chemical preservatives to protect the wood.

Thermally Modified Wood has a similar kiln drying process. The moisture content is reduced to nearly zero, and the molecular structure of the wood is changed with the introduction of high heat. The results of thermal modification are similar to pressure treated, where it protects against outdoor elements. However, it only uses heat over 400 degrees to produce natural rot-resistant wood without chemicals.
Wood color does change with this process. It gives it a deeper brown hue, resembling more tropical woods and walnut.
This modified wood is commonly used for decking, siding, flooring, wall paneling, ceilings, and accent walls.

Our Story

In the 1930s, Edward F. Stanfield Sr. had a 40-cow dairy farm known as Fieldstone Farm in Randallstown, Maryland. Around 1950, the name was changed to E.F. Stanfield and Sons when a partnership was formed with Edward F. Stanfield, Jr., and Richard R. Stanfield. The farm was later moved to its present location and, in 1959, incorporated with the name Edrich Farms, Inc. The new name combined the names of both sons, EDward and RICHard. Also, during this time, a local lumber mill moved to a part of the farm on Old Court Rd. This was eventually purchased by Edrich Farms and became Edrich Lumber, Inc. in April 1962. Richard began the management of the lumber mill, and Edward continued the management of the farm. Over the next few years, the Stanfields could buy adjacent farmlands that increased the Edrich properties to approximately 750 acres.
Family-owned and now 3rd generation-operated, Edrich Lumber is the largest lumber mill and producer of mulches in Baltimore County, Maryland. Under the watchful eye of the current leadership, we have built two new mills and installed countless pieces of state-of-the-art recycling equipment.Our scragg mill utilizes low-grade logs to create lumber for the pallet industry, repurposing innumerable tons of wood that would typically be mulched or burned for fuel. Our new stake mill can make thousands of environmental stakes daily. These stakes are used in eco-friendly filter barriers to help keep our waters clean.Tree stakes are also produced to help young trees take root and flourish in our landscapes.
Many new products are being developed and will be available soon at Edrich Lumber. These product operations will take place in our renovated original mill. One such item is Thermarich wood. The Thermarich process will produce decay-resistant wood for decades without using any chemicals. Decking, sidings, piers, picnic tables, and benches can all be safely used because we use no chemicals in the preservation process.
At Edrich Lumber, no wood scraps go to waste. As a Maryland-licensed recycler of natural clean wood waste, we keep 100 million pounds of wood out of our landfills yearly— recycling, repurposing, and reimagining our business. Edrich Lumber has been creating environmentally safe products for you and your family for more than 60 years.

What Our customers ARe saying

Order Edrich's Thermarich lumber

Message Us to Learn MOre or Place Your Order

Fill out my online form.