Vivariums can be used for hatchlings in the home. Once they reach a certain weight and you get the go ahead from your tortoise vet the tortoise can be kept outdoors for much of the year with access to a secure dry enclosure with heat source. There is no fixed design for building a vivarium. It is really a matter of preference. The one below is an outline of the ones I have used. 

Another example for housing hatchlings, which is being recommended more recently, is the "tortoise table".  My Tortoise vet, however, prefers that hatchlings are kept in vivariums as tortoises can get cold using other methods of housing and then are unable to feed properly; and he has never come across the 'breathing problems', some say, tortoises become prone to which are associated with vivariums. You can learn more about tortoise tables from the Tortoise trust website by clicking here.

CONSTRUCTION

Construct a box from chipboard or similar which is about 36 inches long, 20 inches wide and 16 inches.  Cut out the front of the box and attach two pieces of perspex using guide rails so that they can slide across the front.  Make sure this is higher than the tortoise can stand so that they do not bump into the perspex. Drill plenty of large holes in the ceiling, back and side panels to allow adequate ventilation.

Hang a ceramic heater bulb at the middle/back of the box so that it is out of harms way [from you as well as the tortoises!]. This should also be connected to a suitable thermostat which can be attached to the outside; the thermostat sensor should be placed on the floor of the box under the lamp in the basking area.

Towards the back of the vivarium hang [about nine inches above the hatchlings level] a 'full spectrum fluorescent tube' (available from herpetological suppliers).  These tubes are specially made to provide UVB (ultra violet) light which is necessary to convert vitamin D into its active form.  They have a high Colour Rendering Index (CRI) that imitates natural sunlight. Do not use the domestic type of tube; they are not suitable.

Place a thermometer inside the vivarium in order to keep a check on the temperature, making sure that it is situated away from the heater.  

If you want to stain or varnish the vivarium, ensure you use a non-toxic brand and treat the outside only and leave out in the fresh air in advance of the babies going in to it.

Line the floor with paper such as newspaper.

You may want to put in small wooden boxes for sleeping accommodation; these should be located in the coolest part of the vivarium.

Tortoises like varied terrains so it might help to place a cork mats, a few pieces of flat sandstone and some pieces of tree bark [to hide under] in the vivarium and move these around to find the optimum positions.

Aim for the following:12 hours at night - room temperature; 12 hours at a higher day temperature (approx. 28 C)

For 12 hours at night switch off/have a timer to switch off the fluorescent tube.

During the summer months hatchlings are best kept out of doors in a suitably protected garden pen and placed in the vivarium during the night.

You may need to buy:

Heater - CSE Conical type infra-red element by Pearlco, 100 Watts 220/240 Volts. This I understand has been replaced by a much safer version but you will need to enquire at your suppliers. HabiStat electronic thermostat- heater set at 32 degrees centigrade during the day and 25 at night

Light- Reptisun, 5.0 UVB24"/610mm 20 Watts. Also available from pet shop or vets.

Convertagear - Control unit for fluorescent tubes.

Protector - In case of power surge or electric shock.

Two timer switches for setting the changes in heat and co-ordinating the light to go off at night and on in the morning. Not essential but well worth the time it saves and that you need not trust your memory.

It all sounds complicated I know, but everything should come with easy to follow installation instructions so it sounds worse than it really is.  This little lot will set you back about £120.00, depending on what you have already.

If your suppliers do not have what is on the list do not let them then sell you something similar before being entirely sure it is suitable.  Do not buy a heat pad. These are totally unsuitable for tortoises and are in fact designed for snakes etc. 

Ideas for Furnishing The Tank/ Vivarium

I change the interior contents once a week.

On top of the paper I have a flat brick, tile, slate or rock for placing their food on.  A soft area of fine 'absorbable' grit and something to hide under like torn up tissue or dust free chopped hay or bark.

You must also include a flat dish for shallow drinking water, to be kept clean and topped up daily, a flower pot saucer is good but you can buy purpose made ones from your reptile supplier. Just check that the tortoise can get in and out with out any difficulty.