There are four Construction boosts in OSRS: the crystal saw at +3, a trimmed cup of tea at +3, an orange spicy stew at up to +5, and the Construction cape at +1. The crystal saw is invisible and stacks on top of any one of the others, which makes +8 the ceiling and +6 the largest boost you can rely on.

Everything else about Construction boosting comes down to two rules. Visible boosts do not stack with each other, and the crystal saw only applies to builds that need a saw.

Every Construction boost

BoostAmountVisibilityStacks with sawWorks onRequirements
Crystal saw+3Invisiblen/aSaw-required builds onlyThe Eyes of Glouphrie
Cup of tea (clay)+1VisibleYesAnything ConstructionPOH kitchen
Cup of tea (porcelain)+2VisibleYesAnything Construction23 Construction for the cup
Cup of tea (trimmed)+3VisibleYesAnything Construction67 Construction for the cup
Spicy stew (orange spice)0 to +5, or negativeVisibleYesAnything ConstructionRecipe for Disaster, Freeing Evil Dave
Construct. cape+1VisibleYesAnything Construction99 Construction

The cape is listed for completeness. If you have it, you have 99, and the +1 only matters for the handful of hotspots above that.

Visible and invisible, and why it matters

An invisible boost does not change the number on your skills tab. The game checks it separately when you try to build something. The crystal saw is the only one Construction has.

A visible boost raises the number on your skills tab, and it sets that number rather than adding to it. Drink a trimmed tea at base 84 and you are at 87. Drink another one and you are still at 87. Eat a stew that rolls +2 while you are sitting at 87 from tea, and you drop to 86.

That is the mechanic behind the single most common boosting mistake. Consume one visible boost, check the number, then build.

The saw sits on top of whichever visible boost you are carrying, which gives you these combinations.

CombinationTotalGuaranteed
Crystal saw alone+3Yes
Trimmed tea alone+3Yes
Crystal saw and trimmed tea+6Yes
Spicy stew aloneup to +5No
Crystal saw and spicy stewup to +8No

Crystal saw

The saw comes from a crystal saw seed, awarded for completing The Eyes of Glouphrie. Sing the seed into a saw at the singing bowl in Brimstail’s cave or in Prifddinas.

What it does. Lets you build furniture up to 3 levels above your Construction level, without changing your visible level.

Charges. 28, or 56 if you have completed the medium Western Provinces Diary. When it runs out it reverts to a seed and needs re-singing. It is destroyed on death, and Brimstail will give you a replacement seed if you have neither the seed nor the saw.

When a charge is spent. Only when the invisible boost is actually doing something. Building furniture you already have the base level for costs nothing, which means you can carry it permanently without wasting charges. Building a STASH unit above your level also costs nothing.

What the crystal saw works on

It applies to anything requiring both a saw and a hammer, which is most player-owned house furniture, plus:

  • STASH units, without consuming charges
  • Fire pits
  • Shipbuilding, including Sailing facilities and core boat parts, again without consuming charges on core boat parts

What the crystal saw does not work on

  • Rooms. Building an achievement gallery at level 80 is not something the saw helps with.
  • Garden plants. The spirit tree and the fairy ring in a superior garden use a watering can, not a saw.
  • Placing dungeon monsters.
  • Mahogany Homes contract tiers. The saw will not get you Expert contracts below 70 Construction.

The room exclusion is the one that catches people. There is no point boosting to 83 for an ornate jewellery box if you cannot build the achievement gallery it lives in.

Spicy stew

Orange spice is the Construction colour. The stew is made by adding spice to a bowl of stew and gives a random result.

Doses addedBoost range
1-1 to +1
2-3 to +3
3-5 to +5

Getting the spice. After the Freeing Evil Dave subquest of Recipe for Disaster, take a cat into Evil Dave’s basement and kill hell-rat behemoths. Each one guarding orange spice drops a 4-dose orange spice shaker.

How the roll works. Two separate rolls decide the result: one for direction, one for magnitude. A three-dose stew is as likely to drain you as to boost you, and a zero is common.

Rerolling. There is no way to influence the roll. The practical approach is to bring a stack of stews to the hotspot, eat one, glance at the skills tab, and eat another if the number is wrong. A drained level is not a problem because the next stew resets it.

Budget for it. A build needing +5 exactly needs, on average, several stews. If you are one level short rather than five, a trimmed tea is a better use of your time because it always lands.

POH tea

Tea is the boost most players do not know they have.

CupBoostShelfConstruction for the shelf
Clay+1Wooden shelves 1 or 26
Porcelain+2Wooden shelves 323
Gold trimmed+3Teak shelves 267

The trimmed cup is the one worth having, and 67 Construction is well below any level where you would be boosting for a max house build. Teak shelves 2 cost 3 teak planks, 6 soft clay and 2 gold leaf, so the shelf itself is the expensive part rather than the tea.

What your kitchen needs. A built stove space, a larder, a shelf and a built sink space. Making the tea itself needs 20 Cooking and gives 52 Cooking experience.

Making it.

  1. Take a kettle, a teapot and a cup from the shelf.
  2. Take tea leaves from the larder.
  3. Fill the kettle at the sink, then put it on the stove.
  4. Use the tea leaves on the teapot.
  5. Take the kettle off when it boils, and use it on the teapot with leaves to get four servings.
  6. Pour a cup.

You can also ask a servant to serve tea, and they will serve whatever tier your best kitchen shelf holds.

The catch. The cup vanishes from your inventory the moment you leave the house. The boost itself persists outside, so drink it inside and walk out boosted.

Practical combinations

You needDo this
1 to 3 levels on saw-required furnitureCrystal saw alone, no consumables
1 to 3 levels on a room or a plantTrimmed tea
4 to 6 levels on saw-required furnitureCrystal saw and trimmed tea
4 to 5 levels on a room or a plantSpicy stew, reroll until it lands
7 or 8 levels on saw-required furnitureCrystal saw and spicy stew, reroll

Worked POH examples

These are the boosted floors the wiki records for the builds people actually boost for.

BuildLevelNeeds sawSaw and stewSaw and teaStew alone
Gilded altar75Yes6769
Achievement gallery (room)80No75
Basic jewellery box81Yes7375
Gilded portal nexus82Yes7476
Fairy ring85No80
Fancy jewellery box86Yes7880
Boss lair display87Yes7981
Ornate rejuvenation pool90Yes8284
Occult altar90Yes8284
Ornate jewellery box91Yes8385
Crystalline portal nexus92Yes8486

For a full plan built around those numbers, including what the materials cost and where to stop, see the max house Construction level guide.

Boosts and Sailing

The crystal saw works at the shipwrights’ workbench, which means every repair kit and hull part tier can be reached three levels early. Core boat parts do not consume a charge when built with the boost.

That is the cheapest use of the saw in the game, because you can sit three tiers ahead of your base level indefinitely. The Sailing Construction guide covers the recipes and what they cost.

Common mistakes

Drinking two visible boosts. Tea after stew, or stew after tea. The second one replaces the first and usually lowers it.

Boosting the room instead of the furniture. Rooms need the visible boost. Furniture inside them can use the saw. Plan them as two separate problems.

Assuming the boost is permanent. The build is permanent once made. The level is not. If a hotspot needs to be rebuilt, or you want to upgrade it later, you will need the boost again.

Building an upgrade chain out of order. Jewellery boxes, portal nexuses and pools are sequential. Boosting to the top tier does not let you skip the ones below it, so budget boosts for every step.

Forgetting the saw is destroyed on death. Take it into anything dangerous and you are walking back to Brimstail.

Using a spicy stew for a single level. A trimmed tea is guaranteed, free after the first kitchen, and takes about a minute to make.

Boosts do not change your training plan

None of this affects how you train. A boosted level cannot be used to unlock a faster training method for a full session, because the boost expires and the method requirement does not.

What boosts change is the level you need to stop at. Reaching an ornate pool at base 82 rather than 90 saves nearly three million experience, which is the largest single saving available in the skill.

Put your current experience and a target of 82, 83 or 84 into the OSRS Construction Calculator to see what each boosted target actually costs, and the 1-99 training methods guide for how to get there.

Sources for this Construction boosts guide

Boost sizes, visibility and stacking rules come from the OSRS Wiki temporary skill boost table for Construction and the crystal saw item page, including the saw’s charge behaviour, its Sailing and STASH exceptions and the Mahogany Homes exclusion. Spicy stew dose ranges come from the spicy stew page. Tea tiers, shelf requirements and the kitchen recipe come from the cup of tea pages. Boosted build floors are the wiki’s own stated figures on each furniture page. No prices are quoted in this guide, so nothing here goes stale with the market.