for garden objects

Thermo ash

Dark and resistant

Thermo ash is a heat-treated ash with a chocolate tint throughout. For production, the ash wood is heated to temperatures above 160° C for 24 to 48 hours under oxygen deprivation. Depending on the height and duration of the temperature development, the woods discolor from a light light brown to dark brown.

Thermal treatment increases the rot resistance of the wood. It also reduces water absorption, which in turn minimizes the tendency to swell, shrink and cup, and protects the wood from fungal attack. On the other hand, the susceptibility to longitudinal cracks, e.g. when drilling and screwing in screws, develops negatively. Therefore, the holes must always be pre-drilled during assembly!

Storage box ALVARO with thermal ash seat pad
Storage box ALVARO, covered with dark brown thermo ash

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User information SEAT SUPPLIES

Standard dimensions for seat cushions

from thermo ash

The classic use of thermo-ash is as a decking board. For this reason, especially flat formats are well available. We have chosen 25mm x 120mm as the standard dimension in stock. From it it is possible to make visually harmonious bench seats with a total width of about 500 mm (4x plank with width 120 mm + intermediate spacing). Other dimensions for your special designs are possible after consultation.

Thermo ash seat cover
Thermo ash with standard dimension 25 mm x 120 mm

Thermo ash is a natural product

with all advantages and disadvantages

If you choose thermo-ash as a support for your bench, garden furniture or storage box, you must be aware that wood is a natural product – with all its advantages and disadvantages. Warpage, color differences, cracks, stone inclusions and other irregularities are part of this renewable raw material. Thus, surface cracks are normal and stress cracks are possible even in thermally treated wood. These are normally 1-3 mm wide and cannot be narrowed down to a specific length. Stress cracks occur mostly on the faces because water absorption and release is higher on the faces. The appearance of cracks is not a reason for complaint.

Color differences are a natural characteristic of the renewable raw material due to the inhomogeneous nature of the wood and different growth areas, as is the natural onset of wood graying. However, neither of these factors affects the durability of the seat covers.

Oiling as a means against wood graying

Without oiling, any wood – including thermally treated ash – will turn gray within a few months and take on the silvery appearance typical of wood. Thermo ash has an average life span of up to 20 years in temperate climates. This is not significantly prolonged by oiling. The only purpose of oiling is to delay the graying of wood. To delay this effect, the surface should be treated once or twice a year.

As oil we recommend the viscous linseed oil varnish. To produce linseed oil varnish, linseed oil is boiled under exclusion of air, which changes its consistency. Both oils have been used for centuries as natural wood preservatives. In order for the oil to penetrate as deeply as possible into the wood, we recommend diluting this varnish with turpentine oil and applying it several times if necessary. Linseed oil varnish cures much faster than pure, cold-pressed linseed oil, but it can still take a few days. Attention: For seat covers delivered ex works, check before first use whether the protective oil has already dried completely! The oil closes the pores of the wood, so that dirt can not immediately settle and facilitates cleaning afterwards.

Thermo ash natural grayed
Thermo ash also grays without treatment within a few months.

If you do not want the above mentioned features on your high quality garden objects, we recommend you to choose industrially manufactured seat covers made of RESYSTA®, KEBONY® or black plastic. We will be happy to advise you on the alternatives to wood, with which you can expect perfect, consistent, industrially manufactured quality.

Tender text for GaLaBau, for landscape architects and planners

” Thermo ash, kiln dried, with residual moisture below 20%. Surface planed and sanded on all sides, all edges chamfered 2 x 45°. Surface lightly oiled.”

Everything important at a glance.


Information material

User information SEAT SUPPLIES