A unit house is not finished the day it is installed. ECOS unit houses let you change wall panels, windows and doors after assembly, and replace a worn panel on its own. Here is how that works, with drawings.

1. The frame has three parts

The frame is made of three parts: the roof base, the columns and the floor base. The three are joined with bolts and nuts, so the frame can be taken apart for transport (that is what "knock-down" means).

The roof base and the floor base carry the structure, so each is welded in the factory into a single rigid frame. Welding needs factory equipment and adds cost, but it gives a frame that does not twist however many times it is moved.

Exploded view of the three-part frame: roof base, columns, floor base — Figure 1. The three parts of the frame. The roof and floor bases are welded frames; the columns bolt on.

2. Panels, windows and doors slot in between the columns

Once the frame is up, the wall panels, windows and doors slot in between the columns. No bolts or nuts are used here. They are only slotted in, so taking them out does no damage.

Exploded view of a unit house: floor base, columns, roof, and the wall panels, windows and door as individual pieces — Exploded view. Wall panels, windows and doors are individual pieces; every one simply slots in between the columns.

Inside each panel is injected polyurethane foam insulation. The foam is rigid in itself, so it also stiffens the panel. The skin is 0.3 mm embossed steel sheet, which resists denting when pressed.

Plan section showing a wall panel slotted into the column groove — Figure 2. The panel slots into the column groove. A worn panel is pulled out and replaced on its own.

A long row of prefabricated site offices on a gravel yard — An ECOS installation on a real site

3. So it can be changed later

Because everything slots in, all of this is possible after assembly:

Move windows and doors (just swap a wall panel with a window panel)
Replace one worn panel, right where it is
Take out every panel, window and door and leave only the steel frame
Take the unit apart again and rebuild it somewhere else (nothing gets broken)

Plan view showing windows and a door moved and one worn panel replaced — Figure 3. Windows and the door moved, one worn panel replaced. The frame stays as it is.

4. Connecting units and two storeys

Units can be joined to make more space, or stacked two storeys high. Which sides can join depends on the model.

Model	Sides that can join	Two storeys
Work House (WH / WL)	Both the short end (gable side) and the long side (girder side)	Yes
P-House (PH)	The long 6 m side only	Yes

Diagram of connection directions and two-storey stacking — Figure 4. Connection directions: Work House joins on all four sides, P-House on the long sides only. Both can be two storeys.

A row of air-conditioned prefabricated offices at an upcountry site — An ECOS installation on a real site

5. For buyers and for renters

If you buy: add units when your family or business grows; move windows and doors when room use changes; however long you use it, repair only what is damaged.
If you rent: the unit arrives laid out for your site; when it comes back, the panels are refreshed for the next site.

We build our units for rental work, where a unit is moved again and again. This mechanism exists for exactly that.

See it in person

To rent, contact us; we lay the unit out to suit your site. Related: Welding for repeated moves (worker house rental page) / Container rental prices / W-House specifications

Why the walls, windows and doors of a unit house can be changed after installation (illustrated)