The Eastern Horizons Observatory

Our client requested a 10’x8′ observatory to occupy a position in the garden that benefited from very low easterly horizons. With very little artificial light in the area, the only light would have come from the direction of the house (and more specifically the neighbours). In this photo, we can see the view in the East direction, behind the observatory.

The solution was a rolling east side, reducing the height of the observatory on the east face to approximately that of the adjacent garden wall. The low height was especially important owing to the client’s choice of telescope – a 10″ reflector.

Weather-proofing was especially important to our client, as their location in the far north of England is very exposed. High winds as well as driving horizontal rain are frequently seen, dictating both sturdy construction and comprehensive seals. Home Farm Observatories was therefore a natural choice. Our observatories are the only British designs that benefit from a complete frame (in this instance our sturdiest 4×4 gauge frame) that is self-supporting and independent of the roof and wall panels. Our designs also allow for significant expansion and contraction in the outer cladding – essential to allow for changes in the moisture level of the timber as the weather changes – all whilst keeping the gaps closed to prevent rain ingress.

A further feature in both weather-proofing and low horizons is the drop-down South wall. Invisible when in the “up” position, the top 405mm of the wall can be lowered to make the most of southerly views. Equally, it is raised after the roof is closed to fully seal the southern roof overhang – something that cannot be achieved without this feature.

This design exemplifies the reasons for choosing a custom-designed roll-off. Our client in this instance requested the ability to add a warm room later should he wish to. Very few designs could accommodate this – but for our roll-off it is straightforward. Placing the door at the North-West corner and offsetting the telescope to the South allows creation of a 3′ warm room should the customer require it. The roll-off and drop-down walls allowed us to maintain the lowest horizons whilst ensuring sufficient headroom in the observatory for the customer to stand in a warm room without stooping.

Sometimes the best design is the simplest one. Our high-quality italian-made rolling gear is stainless steel with sealed bearings that move smoothly enough that a 10×8′ roof can be easily rolled off with one hand. You’ll only want our motorised roof if you require automation for remote opening.

Comprehensive pre-planning went into the design to ensure that the optical tube assembly could be accommodated at the correct observing height. It sounds obvious but most of our competitors leave this aspect of the work to their clients! We use computer modelling to check sight lines and determine the ideal height – not just for the walls but also for the floor: it is essential that our clients can comfortably reach their eyepiece!

What often impresses our clients most is the quality of our implementation. Our observatories are built to exceptional tolerances – everything is measured to the millimetre to ensure a perfect fit, smooth operation and high rigidity.

Your garden – particularly your lawn – is protected throughout the building process to minimise the collateral damage that can otherwise occur when working on soft ground. We work hard to minimise any sawdust created from our work on site, and all rubbish is cleared before we leave. We’ll even help you to mount your telescope securely and accurately if you need it… after all we are experienced astronomers as well as joiners!

Rolling Wall

If your best horizons don’t line up with the end wall of the observatory, a rolling wall (essentially part of the wall attached to the rolling roof) is a great way to lower the wall height on one side. These can be on one or both sides of the observatory, and can be combined with a flap on the end wall to provide the best views in more than one direction. Maybe one day, we’ll design one that folds up into a tiny cube, but for now, this is the best way to get “Big Sky” from a roll-off roof observatory!

End Flap

An end flap is a great way to get views closer to the horizon, especially if your observatory is oriented North-South. Generally, the flap is opened after the roof is opened and can reduce viewing angles all the way to the horizontal. This can be combined with one or more rolling walls to dramatically improve the amount of sky that is visible for visual and planetary observers in particular.


Our ‘flat’ roof (it has a slight angle to allow rainwater to drain off) is covered with a single-piece EPDM rubber membrane. The lack of any joints means there’s no leaks, and the tough rubber membrane resists damage by impact or weathering, resulting in an expected 50-year lifespan. Where appropriate, we’ll fit a gutter on the low side to channel water away safely to the ground.