Temperature control

[7013]

Having just moved into my new home and unpacked and stowed most things I find myself with the enviable position of having enough room in my loft to (a) stand upright and (B) build a decent sized layout. Power and lighting are not a problem, the problem is how do I regulate the temperature in the loft. One option that is not open to me is putting a skylight or similar in. The main problem is keeping the place cool (heating is easy). I have mulled over two options, firstly a poratble Air Conditioning Unit (ACU) or secondly a cheaper option in the form of one of those room cooling units which cool the air by circulating it through the machine. In each case venting is probably going to be the problem as I have nowhere to vent these machine which both appear to need it.

I would like some suggestions as to which way to go, it gets very warm and sticky on a sunny day which may affect me more than my layout! so would a straight forward fan help, I am not sure what sort of temperature fluctuations a layout will tolerate before problems occur.

Anyway if anyone has a suggestion I would like to hear it. Thanks in anticipation.

Andi

[34theletterbetweenB&D]

Rather than use energy to remove heat from the loft, the better way is to do as much as possible to limit heat gain. This will mean installing insulation, but it will pay off two fold: not only should you not need to cool the space in summer, you will not need nearly so much heat input to make it comfortable in winter.

 

Sounds simple enough, but insulating a roof is not trivial, and your insurer will have to be informed. I would suggest engaging a chartered surveyor to advise on the right way to go about insulating the roof construction of your property. The last thing you want to do is a DIY bodge job, which might for example cause damp to build up on structural timbers: that is a quick recipe for a very expensive rectification job, which your insurer would very properly decline to cover if it emerged that no qualified advice was obtained.

 

As for the layout, other than items of card or similar construction, it will stand greater temperature extremes than you will find comfortable and still work well.

[7013]

Thanks 34

Your suggestion does sound a viable alternative so I will consider it carefully, I have an air cooler which I experimented with in my conservatory and despite a very hot sun it did cool the room a few degrees, but as you said it is using energy to remove heat rather than preventing heat build up.

[Oldddudders]

I had a new roof put on my 1850 cottage a few years back. This has that modern multi-layer insulation under the tiles - basically it seems to be variously tinfoil and very thin foam sheeting alternated. While we are still not actually "living" upstairs, there is no doubt that very hot days do not bring the temperature up nearly as much as might be expected under the roof. I think this product is available in several "strengths" according to the number of layers - and priced accordingly. Ours is, I think 7-leafed. If you talk to a surveyor or architect about such things, he/she will tell you a lot more, I'm sure.

[trisonic]

My experience has been that it is extremely difficult to cool something below ambient temperature.

Where I live I have Bi-level (a system for each floor) central air conditioning (A/C) and the lofts still get very hot - it depends on what you are comfortable with, we get up to (the highest I've seen) 106f shade temperature outside and 90% humidity, inside the lofts it is always hotter however much the loft is insulated - it will gradually creep up in temperature. I'm not extremist about this I'm comfortable at 78f - the advantage of A/C is that it reduces the humidity by half, roughly.

Obviously our lofts are not part of the A/C (s) systems and there we pull air out with a relatively simple yet powerful fan. As everyone else has said not an easy answer I'm afraid - by the way in the 'States it is normal to have vented eaves then an airspace (from bottom to top) BEFORE insulation is added (with a passive outlet at roof peak) - that helps a lot.

 

This is why Railroaders over here love basements......

Best, Pete.

[Guest Max Stafford]

Being aware that there are important airflow and moisture related issues involved, my approach has been to use the foil 'bubble wrap' only over the working area, then ply it over. Everything else below this Baseboard level and under has been left. Air is still able to move beneath the foil area thus avoiding moisture build up. So far, it has worked well under severe winter conditions. We'll see how it does in the heat now!

 

Dave.

[28XX]

Being aware that there are important airflow and moisture related issues involved, my approach has been to use the foil 'bubble wrap' only over the working area, then ply it over. Everything else below this Baseboard level and under has been left. Air is still able to move beneath the foil area thus avoiding moisture build up. So far, it has worked well under severe winter conditions. We'll see how it does in the heat now!

 

Dave.

 

I would be grateful for any updates on this, if we do get a 'bar-be-que' summer. My intention is to start with that level of insulation and add more if necessary, creating an insulated 'tent' with a pentagonal cross-section inside the loft space. Edit: sketch added.

cross section.pdf

[D803Albion]

I would be grateful for any updates on this, if we do get a 'bar-be-que' summer. My intention is to start with that level of insulation and add more if necessary, creating an insulated 'tent' with a pentagonal cross-section inside the loft space. Edit: sketch added.

cross section.pdf

 

Max has mentioned the most important thing when retro fitting insulation, AIRFLOW. Very important !

 

There are a number of "Multi Foil" space saving insulation on the market, ranging from the cheap to the very expensive.

 

The one I am mostly aware of is Tri iso super 10.

 

I have a sample and a suggested installment guide.

 

I will gladly post it to you if you wish.

[7013]

As with most things railway this subject is as complexed as any, I have installed an airflow cooler which is not an AC unit but does circulate the air well with the addition of a dust filtration and Ionising setting, not entirely sure what the latter does. It also has a water reservoir which can be used to humidify the air if needed, but I suspect I will not need this function. Another aid to air circulation I find is to leave the attic door open which causes an updraft of cooler air.

My main concern was the potebntial effects of temperature on my layout and rolling stock, however I do not think we are going to get extremes which cause warping or any other damage. As I said before I believe the heat affects the human operators more than the layout, it is in teresting though to see peoples approaches to this situation.