Mason's Tools

by VaranSL

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Mason's Tools

Your tools are used to craft structures made of stone, granite, marble, clay and other materials from smaller, individual units that are layered on each other. These structures can provide greater portection than just wooden constructs, though are quite more expensive to build.

Mason's Tools

Mason's tools consist of a trowel, a hammer, a chisel, brushes, and a square. Proficiency with this tool lets you add your proficiency bonus to any Mason's Tools (Strength) checks you make for your structures.

Mason's Tools weigh 8 lbs and cost 10 gp.

Building Materials

Unlike other tools, you need access to large quantities of stone, clay, mortar and other materials. If you find yourself wanting to create a massive castle in the middle of the desert, you may have to ship materials in to work with. This may increase you costs per the DMs discretion.


If you can dream it, you can probably build it with the help of your Mason's Tools... though it may require a large purse of gold and a lot of time.

If you aren't proficient in Mason's Tools, you can still hire others to build the structure, you just can't help.


To begin building your structure, you need a plot of land. If the land lies within a kingdom or similar domain, a royal charter (a legal document granting permission to oversee the estate in the name of the crown) is needed, a land grant (a legal document bequeathing custody of the land to the character for as long as he or she remains loyal to the crown), or a deed (a legal document that serves as proof of ownership). Land can also be acquired by inheritance or other means.


Once you have the necessary paperwork, you can begin construction of your structure. Each day you spend working on your structure, you must expend 25 gp to cover the costs of materials. If you are unable to cover the costs, you are unable to purchase the needed materials and your day of work is wasted.


As an adventurer, you aren't always willing to stay in one spot for a year to build a small fort. By hiring skilled workers, they can keep the progress moving forward on your structure going, though their services cost 2 gp per day. With multiple skilled workers on site, they can expedite the building process, but structures have a maximum number of workers that can work on it at a time.

By hiring skilled workers, you must spend 25 gp per day per worker, plus the worker's wage of 2 gp per day. If you are unable to pay this, than no work is done on your structure.


Only characters and hirelings that are proficient with Mason's Tools can build structures made of stone.


The assumption is that you are building your structures out of simple stone native to the area. By importing or building with expensive materials, like marble, granite, or even adamantine, the cost can increase drastically.

See the chart Exotic Materials below for estimated cost information. The increased cost is subject to DMs discretion.

Exotic Materials
Material Cost Increase AC Damage Threshold Hit Points
per inch
Adamantine x10 20 20 50
Granite x2 17 10 35
Marble x4 17 15 35
Mithral x8 15 15 40
Stone - 15 5 30
Special Properties

A structure built with adamantine cancels out the double damage from seige weapons.
A structure built with mithral is far lighter than regular stone and requires less supporting structures, this means that upon parts of your structure being destroyed, it is less likely to collapse completely, per DM's discretion.

Damage and Repairs

Some adventures requiring you to annoy the orc war bands and they decide to take the fight to you, they may try to attack your structures. Each structure is abstracted out to be built up by 10' x 10' x 6" panels of stone, or whatever material you used to create your structure. Upon your structure being attacked, the attacker determines which panel they would like to target and must roll against the AC of the structure. On a successful hit, they then roll damage. If their damage meets or exceed the damage threshold for your chosen material, then the damage goes through, otherwise the only deal superficial damage and no affect on your

If you wish to repair your structure, you must spend an hour repairing the structure with your Mason's Tools and succeed on a DC 15 Mason's Tools (Strength) check and repair 1d6 + your Strength modifier in hit points to that panel of wall. For each hit point that you restore, it costs you 1 gp in materials. This cost increases per the Exotic Materials chart for different materials.

Types of Structures

You can build a variety of stone structures with your Mason's Tools, each structure requires a different amount of time and total cost. The cost of each structure can be paid for over time, and you can always go back and work on your structure at a later date. See the chart Structures on the next page for more information.

Structure Total Cost
in GP
Days to Build
(Single Worker Only)
Days to Build
(Max Workers Only)
Number of Workers
Acres Required
Abbey 50,000 2,000 400 5 1
Guildhall, Town / City 5,000 200 60 4 0.1
Keep / Small Castle 50,000 2,000 400 5 1
Noble Estate with Manor 25,000 1,000 150 7 0.5
Outpost / Fort 15,000 600 100 6 0.3
Palace / Large Castle 500,000 20,000 1,200 17 10
Temple 50,000 2,000 400 5 1
Tower, Fortified 15,000 600 100 6 0.3
Trading Post 5,000 200 60 4 0.1
Defensive Wall 25 1 1 1 -

Defensive Wall

The defensive wall is a structure built in a quick time frame to help protect from invaders. Each defensive wall built consists of two: 10-foot by 10-foot by 6-inches thick walls, with AC 15 and 30 HP per inch of thickness.

Armies would quickly build several of these across a battlement in the hopes of a more favorable fortification, though wooden palisades are a cheaper option for armies not staying in one sport for very long.

Alternatively, you can decrease the thickness of a panel to 3" and have a wall that is 10-foot by 20-foot.

Only a character proficient in Mason's Tools, and has their tools available, can build a defensive wall, though others can help with an effect determined by the DM.


Certain spells can be used to help speed up, and even reduce, the cost of building your structures.


Having proficiency with Mason's Tools can allow you to use the Fabricate spell to help produce your Structure. When casted, you must have the materials present and you can shape them into part of your structure, though only in 5' cubes. For every casting of the Fabricate spell, you decrease the number of days needed to build the structure, for an individual worker, by half a day but the cost of the materials must still be paid (12.5 gp per casting on Stone).

Wall of Stone

At higher levels, the Wall of Stone spell can help build your structures faster, and with less cost per day. For every casting of the Wall of Stone spell, decrease the number of days needed to build the structure, for an individual worker, by 5 days and the cost associated for those day is only the spellcaster's wage, if any. This spell, to create a proper structure, must be cast from someone with Proficiency in Mason's Tools, or guided by someone proficient in Mason's Tools.

This spell only works for Structures built of stone.


Your knowledge of masonry allows you to spot weak points in brick walls. On a successful DC 15 Mason's Tools (Strength) check, you deal double damage to a structure with your weapon attacks.


You can build structures faster by having workers work around the clock. To do this, you must expend 75 gp per day plus 6 gold for wages and this means that for each worker and day you do this for, they do double the amount of work per day.

I.e. If you wish to build a Defensive Wall with Overtime, you would pay 75 gp + 6 gold for wages and you could create two Defensive Walls in 1 day. If you wish to build an Abbey with ovetime, you could do so in 200 days and spend 375 gp + 30 gp per day (3 shifts, 5 workers per shift). This would increase your cost to 81,000 gp.



Setbacks on next page

Variant: Setbacks

When building a structure, sometimes problems can come up that aren't foreseen. At the DMs discretion, you can roll on the Setback chart below.

These setbacks are just natural parts of working on a structure, and normally are absorbed by the costs of materials. This is a great way for the DM to create set ups for quests, for maybe the creatures stealing materials are skeletons that have been ordered to rebuild part of their underground tomb by a necromancer. Or there is supernatural weather at work stopping any shipments of materials from coming through, and its up to the party to figure out why 5-feet of snow dropped in the middle of summer.

d6 Effect
Bad Workers Unfortunately the workers hired understand nothing about masonry and have halted progress on your Structure for 1d4 days. For each day they halted progress, lose that many days and half the gold due to destroyed materials.
Stolen Materials Materials were stolen from the Structure. 1d3 days worth of materials was stolen from the Structure.
Poor Quality The latest materials ordered are falling apart and are useless for building. For new materials, you must wait 1d4 days.
Bad Weather The weather has halted work on your Structure for 1d6 days. There is a 15% chance that the weather was so bad that it destroyed part of the Structure, you lost 1d3 days worth of materials.
Delayed Shipments The shipment of materials has been delayed for 1d6 days.
Out of Stock The materials are out of stock and you must 1d6 days for more to arrive... or spend double on materials for 1d6 days

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