Currently in the construction business there are pretty much two different ways one can build a house, according to inventor and carpenter David Ward.
Inventor David Ward explains the operation of his Strawjet machine, which uses a modified John Deere combine to convert hay into a fabricated wood product that can be used in construction.
The efficient way is to use the traditional stud frame model made with lumber. Then there is the more ecologically friendly method of using either adobe, cement or strawbales — which eliminates a lot of toxic chemicals and less-renewable resources in a particular building, but is much more labor intensive.
But Ward thinks his company, StrawJet, has devised a system of making the more environmentally sound method of haybale construction almost as efficient as building with wood. With the help of the Ashland School of Environmental Technology and a $70,000 grant from the Environmental Protection Agency, he has created a machine that can turn a hayfield into a large amount of ready-to-build-with construction material just as easily as a farmer could bale a bundle of hay for feed.
“You start in the field and end up with an apartment complex with not a lot of interface with other technologies in between,” he said.
“The StrawJet is like a hybrid baler,” Ward said, as he explained how his invention works. “It basically replaces the function of a baler.”
Step by Step
Making strawbale construction blocks may become easier as a result of the StrawJet, but it is still a somewhat complicated process to understand. Here is a step-by-step look at how the StrawJet turns a field of wheat into ready-to-use building material:1) The StrawJet is actually a modified John Deere mower that leaves the cut hay in two skinny rows behind it.
2) A separate trailer, this one designed from scratch by inventor David Ward and his team, either follows behind or makes a second pass and captures the long, skinny row of cut hay and puts it on a conveyor belt.
3) The conveyor belt runs the hay through a circular apparatus that binds the skinny tubes of hay together with string and then adjoins the two together by coating them with the cement-like mineral-based plaster material.
4) The finished product is then dropped back in the field and is ready to build with. If the test cut this autumn goes according to plan, Ward says he is going to begin working on a larger version of the StrawJet that will accomplish all the steps in this process in one pass. He has his eyes on a 1977 John Deere combine for the job.
— Robert Plain
Actually, it’s more like a modified haybaler with an extra function. Its first function is to bale the cut hay into a pair of two-inch thick, continuous strands of hay. “It comes out like toothpaste,” he said.
The second, he said, is to group four of these strands together using a mineral coating — made of fiber adobe, recycled paper and subsoil — into six-inch thick blocks that can be picked right from the field and put together to make a kind of building block.
“It’s kind of unique unto itself,” Ward said. “The thing it is closest to is masonry-style blocks.”
Strawbale construction and other non-stud frame construction methods, he says, are already a popular style of building houses throughout the southwestern United States and around the world, adding that using timber to build houses in pretty much only still utilized in this country.
“Plastered oriented straw is actually a very old building technique,” he said, noting that homes have been built using this method in Asia for thousands of years. “What we are doing is automating it.”
He said the difference between standard haybale construction material and his invention lies in how it is produced and how it can be used. His haybales are only a few inches thick, making it practical to use on interior as well as exterior walls. And, more importantly, with the advent of the StrawJet — the machine that cuts field and creates the blocks in one shot — much of the labor involved in making strawbale construction materials is erased.
“We have competitors who make strawbales in a factory,” Ward said. “Our factory moves through the field. The advantage is our machine is way cheaper than the factory yet our output is similar.”
Because the StrawJet’s bales are much smaller than the variety currently in use, Ward believes his variety could become the first to be used on a large scale construction project.
“Nobody has built a 90-unit apartment out of strawbale because it’s too thick and cumbersome,” he said. “For an apartment complex this would be perfect because of the volume we can produce and it’s more uniform and versatile than other strawbale.”
The StrawJet will be tested on this fall’s crop of wheat. If the prototype works as Ward expects it to, he plans to build an improved StrawJet out of a 1977 John Deere combine that will be able to accomplish twice the output of the current model.
“We’ve got lots of people who are interested in using it,” he said, noting that he has been discussing its use with contractors from as close as Jacksonville and as far away as Colorado. The technology would also likely become popular in the Santa Fe, N.M., area, as, he said, strawbale construction is already the norm in that part of the US.
The international market, he said, for the haybales — or strawcore, as he called the material — is potentially endless.
“Timber is an issue in this country,” he said. “Straw is an annually replenished perpetual resource. It’s a green alternative [for] house construction.”
He said the areas where it could have the greatest effects are the places where lumber is not readily available.
In Afghanistan, where homes are primarily built from adobe blocks, the strawcore could revolutionize the rebuilding of that country.
“Wheat is the one of the biggest crops in Afghanistan,” he said, “It’s a situation where they are almost devoid of building material, unless they use this technology.”
StrawJet has also recently sent a representative to China to see if their new technology could aid in the further development of this country.
“In the next 12 years, China plans to build as many house as are currently in the United States but they don’t have enough materials to build all that,” he said. “But they have everything they need if they use this material.”
Ward began to develop the StrawJet technology 13 years ago when he realized he had to get out of the traditional construction field.
“My doctor told me my blood chemistry read like a list of industrial solvents,” he said. “I thought, ‘There has got to be another way.’”
So he began to experiment with cobb — a form of mud construction and strawbale. While he appreciated the environmental aspects of working with these materials, he also recognized that they were not as easy to build with.
“I wanted to marry the two methods — the speed and uniformity with the non-toxic materials,” he said. “This is my solution.”