I don't think the comment "... what would we know, we only do it every day.." or words to that effect are meant as sarcastic. In fact the man is stating a very obvious point. Although three or four installers might have different approaches, they are professionals who are providing an insight into the problem going on very little detail. If these guys were on site they would resolve the issue in next to no time. Unfortunately, as installers we are always governed by what the customer can afford or wants to spend.
I pass through Monmouth quite frequently on my way to Hartpury in Gloucester, and during my first few trips often got lost on the many winding country lanes when I thought I was taking a shortcut. So I have a slightly brief idea of what your location might look like.
You have a converted barn, which is indicitive of the probability that this was once a farm, and may well still be so on a smaller scale. The comments on whether bells should be first or last are not without merit and deserve some thought, together with the voice 'annunciation' possibility. I also endorse the 'sound bomb' comment (don't concern yourself with what that is for the moment) but the four piezzo has a current drain of about 400 milliamps and there is only so much that a control panel can 'dish out'. So there may be a requirement for extra PSU's ( power supply units) and relays. The cost is minimal. I also go along with the comment that these 'numpties' are not the most sophisticated and will 'fall for the simplest deterrent'.
When installers mention these things, they are doing so in good faith and with your best interests at heart. Looking again at the concept of 'voice annunciation' and 'bells' and 'lights', we must consider whether or not these options are positioned to gain the overall effect of deterring the potential intruder. For example, bells positioned at one point on the property may well be effective if the intruder approaches from that direction. An intruder approaching from an entirely different direction may be totally unperterbed by the sound, particularly in high winds or adverse weather condition. All the security engineers involved with this post know of the EDL phenomena.
Since the barn is 100 yards from the main building, and there is also a workshop, the property in total is fairly spread out. You do not state how many people occupy your premises, their ages nor their physical capacity. I wouldn't expect you to do so, since your initial query relates strictly to 'security devices'. However, this is a factor, together with the proprietary question of 'Is the property ever left empty for long periods ?'.
From your description of the location and access, it is possible to gain entry on to your land from all compass points, you have already stated that an intrusion initially commenced from, shall we say 'across the fields'. There is also the distraction element to be considered, where you are led to believe that intruders are encroaching in one area, when the main thrust, as it were, is continuing from another.
They may have the best of intentions, but it might be better if you were to take the comments regarding the invincibility of the patio doors with a pinch of salt.
In a nutshell, before you make a final decision, arm yourself with a pair of binoculars and look at the surrounding area from first floor windows. What can you see ? where are the blind spots ? Wherever you can see, they also can see your property from that vantage point.
It is pointless securing a building which is 100 yards from the main premises if it is prone to attack in what our friend earlier called 'the silly hours'. The chance of you being alerted are slim. You therefore need to connect both properties to each other by way of cable or wireless signal. There is a possibility that at 100 yards, the interconnecting cable shall be subject to voltage loss (don't worry about this for the moment) but this can be overcome. Likewise, the workshop should also have a permanent interconnection with the main premises. In heavy winds, the sound from the bells or sirens, or whatever you use, can simply float in the opposite direction to you.
1) Interconnection of all buildings.
This is cheaper and simpler than people think. It can be achieved in just a few hours and provided you are in good health there is no need to bring in a contractor to do the job for you.
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It is a fair assumption that you do not know the total number of people using the tracks and surrounding areas. You should, since some individuals who rarely use these routes may well crop up for a week or so innocently walking their dogs (these are the characters who do not do anything innocently), they should be monitored, and since we do not have eyes in the backs of our heads we need something that does. The cheapest answer is in 24 hour DVR recording with CCTV cameras.
2) 24 hour cctv coverage.
Again, interconnecting as in 1 above. Are you acting illegaly using this method ? Well, not according to a friend of mine in the police force. You may video or photograph in any public place, currently there is no law preventing you from doing so. Were you to progress this route, you do not have to confine the cameras to the walls of your buildings, we have placed them in some ridiculous positions before now. It is worth mentioning, although it doesn't apply in your case, that you are not allowed to place a security camera where it is overlooking a neighbour's property and also that it is in your interests to mount most of the cameras in a highly visible position. If you have looked from your property with binoculars, there is no reason why others can not 'case' you using the same method, thus seeing the cameras. Careful positioning and overlap of cameras is vital to cover 'black spots'.
There are drawbacks in CCTV .... fog is a major culprit but this is not prevalent every day or night of the year. River fog, a phenomena which occurs at night and in certain weather conditions is usually confined to the immediate area, i.e. the banks and possibly a few metres from the banks of the river, but it should nevertheless be taken into consideration.
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Probably your biggest outlay, and one I would consider essential (others may disagree but their viewpoints are always valid) is a 'Dialler' which is capable of sending a message to say four or five numbers, this is normal for modern units anyway. A good one should be less than £100 but don't buy a 'cheapy'. If you could afford two, one using landline and another dedicated solely to 'wire free' transmission (think of a mobile phone) then so much the better. The reason for two is simply to ensure that there is a back up.
3) Remote signalling... Dialler.
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Lighting the grounds of the property has so far been a contentious issue in this series of posts, and with good reasons put forward. However, I am persuaded that a full 'flood' of the entire grounds is not without merit. Personally, I am not a fan of the 'bog standard' off the shelf units which incorporate a floodlight and detector. It is preferable to use seperate lights and detectors, with the capacity to turn on all or each of the lights from the main premises if necessary. It would be in your favour if the flood lighting was linked to the CCTV system via a switch which could turn the lights off during the day, a relay (don't concern yourself with 'relay' for the time being, it is a very simple procedure) would be required in this case.
4) Complete lighting coverage of all areas.
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I have a tendency to agree with the engineer who stated that sound should be introduced a few seconds before lighting. He states good grounds for this. Put in it's simplest form, if a relative came into your bedroom to wake you, then he or she would turn the light on and virtually at the same time 'call your name'. If that same relative did not turn the light on in your bedroom and call your name, you would be disorientated for a few seconds. That is the principle behind his statement, 'initial noise in the dark' always disorientates the best of us.
But these sounders, bells or sirens, call them what you will, should be positioned at every vantage point. A warning device is useless unless it is virtually 'on top' of the intruder. Here again, we are looking at the use of 'power supply units' and 'relays' which is not a costly job, nor technical, to achieve yourself.
5) External Warning at every location.
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There is no number six at the moment since it involves external dual infra red barriers and can be quite costly, but it is worth mentioning your fences. I don't know how long you've lived in the country, but a fence is no barrier to a fox, he'll find a way around, under, over or through it. This applies equally to the intruder. If he is intent on gaining access, no fence is going to stop him.
These are my own views based on my experiences protecting second homes in Mid Wales. At that time, some sort of Welsh nationalists were intent on burning down properties .... most of which were not second homes. Therefore, I would appreciate the input of younger engineers who have different and often better advice.
